Thales of Miletus ( ; grc-gre,
Θαλῆς
Thales of Miletus ( ; grc-gre, wikt:Θαλῆς, Θαλῆς; ) was a Greeks, Greek Greek Mathematics, mathematician, astronomer, statesman, and Pre-Socratic philosophy, pre-Socratic philosopher from Miletus in Ionia, Asia Minor. He was one of ...
; ) was a
Greek
Greek may refer to:
Greece
Anything of, from, or related to Greece, a country in Southern Europe:
*Greeks, an ethnic group.
*Greek language, a branch of the Indo-European language family.
**Proto-Greek language, the assumed last common ancestor ...
mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems.
Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change.
History
On ...
,
astronomer
An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, g ...
, statesman, and
pre-Socratic philosopher
Pre-Socratic philosophy, also known as early Greek philosophy, is ancient Greek philosophy before Socrates. Pre-Socratic philosophers were mostly interested in cosmology, the beginning and the substance of the universe, but the inquiries of thes ...
from
Miletus
Miletus (; gr, Μῑ́λητος, Mī́lētos; Hittite transcription ''Millawanda'' or ''Milawata'' (exonyms); la, Mīlētus; tr, Milet) was an ancient Greek city on the western coast of Anatolia, near the mouth of the Maeander River in a ...
in
Ionia
Ionia () was an ancient region on the western coast of Anatolia, to the south of present-day Izmir. It consisted of the northernmost territories of the Ionian League of Greek settlements. Never a unified state, it was named after the Ionian ...
,
Asia Minor
Anatolia, tr, Anadolu Yarımadası), and the Anatolian plateau, also known as Asia Minor, is a large peninsula in Western Asia and the westernmost protrusion of the Asian continent. It constitutes the major part of modern-day Turkey. The re ...
. He was one of the
Seven Sages of Greece
The Seven Sages (of Greece) or Seven Wise Men (Greek: ''hoi hepta sophoi'') was the title given by classical Greek tradition to seven philosophers, statesmen, and law-givers of the 7–6th century BC who were renowned for their wisdom.
The S ...
. Many, most notably
Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...
, regarded him as the first philosopher in the
Greek tradition,
and he is otherwise historically recognized as the first individual known to have entertained and engaged in
scientific philosophy.
[Frank N. Magill]
''The Ancient World: Dictionary of World Biography'', Volume 1
Routledge, 2003 He is often referred to as the Father of Science.
Thales is recognized for breaking from the use of
mythology
Myth is a folklore genre consisting of narratives that play a fundamental role in a society, such as foundational tales or origin myths. Since "myth" is widely used to imply that a story is not objectively true, the identification of a narrat ...
to explain the world and the universe, instead explaining natural objects and phenomena by offering
naturalistic theories
A theory is a rational type of abstract thinking about a phenomenon, or the results of such thinking. The process of contemplative and rational thinking is often associated with such processes as observational study or research. Theories may be s ...
and
hypotheses
A hypothesis (plural hypotheses) is a proposed explanation for a phenomenon. For a hypothesis to be a scientific hypothesis, the scientific method requires that one can test it. Scientists generally base scientific hypotheses on previous obser ...
. Almost all the other
pre-Socratic philosophers
Pre-Socratic philosophy, also known as early Greek philosophy, is ancient Greek philosophy before Socrates. Pre-Socratic philosophers were mostly interested in cosmology, the beginning and the substance of the universe, but the inquiries of the ...
followed him in explaining nature as deriving from a unity of everything based on the existence of a single ultimate substance instead of using mythological explanations.
Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...
regarded him as the founder of the
Ionian School of philosophy, and reported Thales' hypothesis that the
originating principle of
nature
Nature, in the broadest sense, is the physics, physical world or universe. "Nature" can refer to the phenomenon, phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. ...
and the nature of
matter
In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic partic ...
was a single material
substance:
water
Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...
.
In
mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
, Thales used
geometry
Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is c ...
to calculate the heights of pyramids and the distance of ships from the shore. He is the first known individual to use
deductive reasoning
Deductive reasoning is the mental process of drawing deductive inferences. An inference is deductively valid if its conclusion follows logically from its premises, i.e. if it is impossible for the premises to be true and the conclusion to be fals ...
applied to geometry by deriving four corollaries to
Thales' theorem
In geometry, Thales's theorem states that if A, B, and C are distinct points on a circle where the line is a diameter, the angle ABC is a right angle. Thales's theorem is a special case of the inscribed angle theorem and is mentioned and proved ...
. He is also the first known to whom a
mathematical discovery has been attributed.
Life
![Griechischen und phönizischen Kolonien](https://upload.wikimedia.org/wikipedia/commons/a/a9/Griechischen_und_ph%C3%B6nizischen_Kolonien.jpg)
The dates of Thales' life are not exactly known, but are roughly established by a few datable events mentioned in the sources. According to
Herodotus
Herodotus ( ; grc, , }; BC) was an ancient Greek historian and geographer from the Greek city of Halicarnassus, part of the Persian Empire (now Bodrum, Turkey) and a later citizen of Thurii in modern Calabria ( Italy). He is known f ...
, Thales predicted the
solar eclipse of 28 May 585 BC.
[Herodotus]
1.74.2
and A. D. Godley's footnote 1; Pliny
2.9 (12)
and Bostock's footnote 2. Diogenes Laërtius
Diogenes Laërtius ( ; grc-gre, Διογένης Λαέρτιος, ; ) was a biographer of the Ancient Greece, Greek philosophers. Nothing is definitively known about his life, but his surviving ''Lives and Opinions of Eminent Philosophers'' is a ...
quotes the chronicle of
Apollodorus of Athens
Apollodorus of Athens ( el, Ἀπολλόδωρος ὁ Ἀθηναῖος, ''Apollodoros ho Athenaios''; c. 180 BC – after 120 BC) son of Asclepiades, was a Greek scholar, historian, and grammarian. He was a pupil of Diogenes of Babylon, Pan ...
as saying that Thales died at the age of 78 during the 58th
Olympiad
An olympiad ( el, Ὀλυμπιάς, ''Olympiás'') is a period of four years, particularly those associated with the ancient and modern Olympic Games.
Although the ancient Olympics were established during Greece's Archaic Era, it was not until ...
(548–545 BC) and attributes his death to
heat stroke
Heat stroke or heatstroke, also known as sun stroke, is a severe heat illness that results in a body temperature greater than , along with red skin, headache, dizziness, and confusion. Sweating is generally present in exertional heatstroke, ...
while watching the games. Thales was probably born in the city of Miletus around the mid-620s BC. The ancient writer
Apollodorus of Athens
Apollodorus of Athens ( el, Ἀπολλόδωρος ὁ Ἀθηναῖος, ''Apollodoros ho Athenaios''; c. 180 BC – after 120 BC) son of Asclepiades, was a Greek scholar, historian, and grammarian. He was a pupil of Diogenes of Babylon, Pan ...
writing during the 2nd century BC,
thought Thales was born about the year 625 BC.
Ancestry and family
Herodotus
Herodotus ( ; grc, , }; BC) was an ancient Greek historian and geographer from the Greek city of Halicarnassus, part of the Persian Empire (now Bodrum, Turkey) and a later citizen of Thurii in modern Calabria ( Italy). He is known f ...
, writing in the 5th century BC, described Thales as "a
Phoenicia
Phoenicia () was an ancient thalassocratic civilization originating in the Levant region of the eastern Mediterranean, primarily located in modern Lebanon. The territory of the Phoenician city-states extended and shrank throughout their histor ...
n by remote descent".
The later historian
Diogenes Laërtius
Diogenes Laërtius ( ; grc-gre, Διογένης Λαέρτιος, ; ) was a biographer of the Ancient Greece, Greek philosophers. Nothing is definitively known about his life, but his surviving ''Lives and Opinions of Eminent Philosophers'' is a ...
, in his third century AD ''
Lives of the Philosophers'', references Herodotus,
Duris, and
Democritus
Democritus (; el, Δημόκριτος, ''Dēmókritos'', meaning "chosen of the people"; – ) was an Ancient Greek pre-Socratic philosopher from Abdera, primarily remembered today for his formulation of an atomic theory of the universe. No ...
, who all agree "that Thales was the son of Examyas and Cleobulina, and belonged to the Thelidae who are Phoenicians and amongst the noblest descendants of
Cadmus
In Greek mythology, Cadmus (; grc-gre, Κάδμος, Kádmos) was the legendary Phoenician founder of Boeotian Thebes. He was the first Greek hero and, alongside Perseus and Bellerophon, the greatest hero and slayer of monsters before the da ...
and
Agenor
Agenor (; Ancient Greek: Ἀγήνωρ or Αγήνορας ''Agēnor''; English language, English translation: "heroic, manly") was in Greek mythology and history a Phoenician monarch, king of Tyre, Lebanon, Tyre or Sidon. The Dorians, Doric Gr ...
" who had been banished from Phoenicia and that Thales was enrolled as a citizen in Miletus along with
Neleus.
Friedrich Nietzsche
Friedrich Wilhelm Nietzsche (; or ; 15 October 1844 – 25 August 1900) was a German philosopher, prose poet, cultural critic, philologist, and composer whose work has exerted a profound influence on contemporary philosophy. He began his ...
interprets this as meaning "only that his forefathers belonged to the seafaring people of
Cadmus
In Greek mythology, Cadmus (; grc-gre, Κάδμος, Kádmos) was the legendary Phoenician founder of Boeotian Thebes. He was the first Greek hero and, alongside Perseus and Bellerophon, the greatest hero and slayer of monsters before the da ...
".
However, Diogenes Laërtius then reports of a conflicting account, stating that: "Most writers, however, represent him as a genuine Milesian and of a distinguished family". In addition, his supposed mother, Cleobulina, has also been described as his companion instead of his mother.
The probability is that Thales was as Greek as most Milesians.
It is possible that he was of mixed ancestry as his ancestors were likely
Cadmeians from
Boeotia
Boeotia ( ), sometimes Latinized as Boiotia or Beotia ( el, Βοιωτία; modern: ; ancient: ), formerly known as Cadmeis, is one of the regional units of Greece. It is part of the region of Central Greece. Its capital is Livadeia, and its lar ...
coupled with the fact of his father having a
Carian
The Carian language is an extinct language of the Luwic subgroup of the Anatolian branch of the Indo-European language family. The Carian language was spoken in Caria, a region of western Anatolia between the ancient regions of Lycia and Lydia, ...
name. ''
Encyclopedia Britannica
An encyclopedia (American English) or encyclopædia (British English) is a reference work or compendium providing summaries of knowledge either general or special to a particular field or discipline. Encyclopedias are divided into articles ...
'' (1952) concluded that Thales was most likely a native Milesian of noble birth and that he was certainly a
Greek
Greek may refer to:
Greece
Anything of, from, or related to Greece, a country in Southern Europe:
*Greeks, an ethnic group.
*Greek language, a branch of the Indo-European language family.
**Proto-Greek language, the assumed last common ancestor ...
.
Diogenes continues, by delivering more conflicting reports: one that Thales married and either fathered a son (
Cybisthus or
Cybisthon) or adopted his nephew of the same name; the second that he never married, telling his mother as a young man that it was too early to marry, and as an older man that it was too late.
Plutarch
Plutarch (; grc-gre, Πλούταρχος, ''Ploútarchos''; ; – after AD 119) was a Greek Middle Platonist philosopher, historian, biographer, essayist, and priest at the Temple of Apollo in Delphi. He is known primarily for his ''P ...
had earlier told this version:
Solon
Solon ( grc-gre, Σόλων; BC) was an Athenian statesman, constitutional lawmaker and poet. He is remembered particularly for his efforts to legislate against political, economic and moral decline in Archaic Athens.Aristotle ''Politics'' ...
visited Thales and asked him why he remained single; Thales answered that he did not like the idea of having to worry about children. Nevertheless, several years later, anxious for family, he adopted his nephew Cybisthus.
Travels
Some assume that Thales, at one point in his life, visited
Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...
, where he learned about geometry.
It is not impossible that Thales visited Egypt, since Miletus had a permanent colony there (namely
Naucratis
Naucratis or Naukratis (Ancient Greek: , "Naval Command"; Egyptian: , , , Coptic: ) was a city and trading-post in ancient Egypt, located on the Canopic (western-most) branch of the Nile river, south-east of the Mediterranean sea and the city ...
), however visits to Egypt were a commonplace attribution to various philosophers by later writers, especially when these writers tried to explain mathematical knowledge. However, Thales may have known about Egypt from accounts of others, without actually visiting it. There is no strong evidence that Thales ever visited countries in the
Near East
The ''Near East''; he, המזרח הקרוב; arc, ܕܢܚܐ ܩܪܒ; fa, خاور نزدیک, Xāvar-e nazdik; tr, Yakın Doğu is a geographical term which roughly encompasses a transcontinental region in Western Asia, that was once the hist ...
.
Activities
Thales (who was born about 50 years before
Pythagoras
Pythagoras of Samos ( grc, Πυθαγόρας ὁ Σάμιος, Pythagóras ho Sámios, Pythagoras the Samos, Samian, or simply ; in Ionian Greek; ) was an ancient Ionians, Ionian Ancient Greek philosophy, Greek philosopher and the eponymou ...
and 300 years before
Euclid
Euclid (; grc-gre, Wikt:Εὐκλείδης, Εὐκλείδης; BC) was an ancient Greek mathematician active as a geometer and logician. Considered the "father of geometry", he is chiefly known for the ''Euclid's Elements, Elements'' trea ...
) is often hailed as "the first Greek mathematician".
While some historians, such as Colin R. Fletcher, point out that there could have been a predecessor to Thales who would have been named in Eudemus' lost book ''History of Geometry'', it is admitted that without the work "the question becomes mere speculation."
Fletcher holds that as there is no viable predecessor to the title of first Greek mathematician, the only question is whether Thales qualifies as a practitioner in that field; he holds that "Thales had at his command the techniques of observation, experimentation, superposition and deduction...he has proved himself mathematician."
Aristotle wrote in Metaphysics, "Thales, the founder of
this school of philosophy, says the permanent entity is water (which is why he also propounded that the earth floats on water). Presumably he derived this assumption from seeing that the nutriment of everything is moist, and that heat itself is generated from moisture and depends upon it for its existence (and that from which a thing is generated is always its first principle). He derived his assumption from this; and also from the fact that the seeds of everything have a moist nature, whereas water is the first principle of the nature of moist things."
[
Thales involved himself in many activities, including ]engineering
Engineering is the use of scientific method, scientific principles to design and build machines, structures, and other items, including bridges, tunnels, roads, vehicles, and buildings. The discipline of engineering encompasses a broad rang ...
. Some say that he left no writings. Others say that he wrote ''On the Solstice
A solstice is an event that occurs when the Sun appears to reach its most northerly or southerly excursion relative to the celestial equator on the celestial sphere. Two solstices occur annually, around June 21 and December 21. In many countr ...
'' and ''On the Equinox
A solar equinox is a moment in time when the Sun crosses the Earth's equator, which is to say, appears directly above the equator, rather than north or south of the equator. On the day of the equinox, the Sun appears to rise "due east" and se ...
''. The ''Nautical Star-guide'' has been attributed to him, but this was disputed in ancient times. No writing attributed to him has survived. Diogenes Laërtius quotes two letters from Thales: one to Pherecydes of Syros
Pherecydes of Syros (; grc-gre, Φερεκύδης ὁ Σύριος; fl. 6th century BCE) was an Ancient Greek mythographer and proto-philosopher from the island of Syros. Little is known about his life and death. Some ancient testimonies coun ...
, offering to review his book on religion, and one to Solon
Solon ( grc-gre, Σόλων; BC) was an Athenian statesman, constitutional lawmaker and poet. He is remembered particularly for his efforts to legislate against political, economic and moral decline in Archaic Athens.Aristotle ''Politics'' ...
, offering to keep him company on his sojourn from Athens
Athens ( ; el, Αθήνα, Athína ; grc, Ἀθῆναι, Athênai (pl.) ) is both the capital and largest city of Greece. With a population close to four million, it is also the seventh largest city in the European Union. Athens dominates ...
.
Olive story as example of option type trade
A story, with different versions, recounts how Thales achieved riches from an olive harvest by prediction of the weather. In one version, he bought all the olive presses
Olive oil extraction is the process of extracting the oil present in olive drupes, known as olive oil. Olive oil is produced in the mesocarp cells, and stored in a particular type of vacuole called a lipo vacuole, i.e., every cell contai ...
in Miletus after predicting the weather and a good harvest for a particular year. Another version of the story has Aristotle explain that Thales had reserved presses in advance, at a discount, and could rent them out at a high price when demand peaked, following his prediction
A prediction (Latin ''præ-'', "before," and ''dicere'', "to say"), or forecast, is a statement about a future event or data. They are often, but not always, based upon experience or knowledge. There is no universal agreement about the exact ...
of a particularly good harvest. This first version of the story would constitute the first historically known creation and use of futures
Futures may mean:
Finance
*Futures contract, a tradable financial derivatives contract
*Futures exchange, a financial market where futures contracts are traded
* ''Futures'' (magazine), an American finance magazine
Music
* ''Futures'' (album), a ...
, whereas the second version would be the first historically known creation and use of options.
Aristotle explains that Thales' objective in doing this was not to enrich himself but to prove to his fellow Milesians that philosophy could be useful, contrary to what they thought, or alternatively, Thales had made his foray into enterprise because of a personal challenge put to him by an individual who had asked why, if Thales was an intelligent famous philosopher, he had yet to attain wealth.
Advisor role
Diogenes Laërtius
Diogenes Laërtius ( ; grc-gre, Διογένης Λαέρτιος, ; ) was a biographer of the Ancient Greece, Greek philosophers. Nothing is definitively known about his life, but his surviving ''Lives and Opinions of Eminent Philosophers'' is a ...
tells us that Thales gained fame as a counselor when he advised the Milesians not to engage in a symmachia, a "fighting together", with the Lydians. This has sometimes been interpreted as an alliance. Another story by Herodotus is that Croesus
Croesus ( ; Lydian: ; Phrygian: ; grc, Κροισος, Kroisos; Latin: ; reigned: c. 585 – c. 546 BC) was the king of Lydia, who reigned from 585 BC until his defeat by the Persian king Cyrus the Great in 547 or 546 BC.
Croesus was ...
sent his army to the Persian territory. He was stopped by the river Halys, then unbridged. Thales then got the army across the river by digging a diversion upstream so as to reduce the flow, making it possible to cross the river. While Herodotus reported that most of his fellow Greeks believe that Thales did divert the river Halys to assist King Croesus' military endeavors, he himself finds it doubtful.
Croesus was defeated before the city of Sardis
Sardis () or Sardes (; Lydian: 𐤳𐤱𐤠𐤭𐤣 ''Sfard''; el, Σάρδεις ''Sardeis''; peo, Sparda; hbo, ספרד ''Sfarad'') was an ancient city at the location of modern ''Sart'' (Sartmahmut before 19 October 2005), near Salihli, ...
by Cyrus
Cyrus ( Persian: کوروش) is a male given name. It is the given name of a number of Persian kings. Most notably it refers to Cyrus the Great ( BC). Cyrus is also the name of Cyrus I of Anshan ( BC), King of Persia and the grandfather of Cyrus ...
, who subsequently spared Miletus because it had taken no action. Cyrus was so impressed by Croesus’ wisdom and his connection with the sages that he spared him and took his advice on various matters. The Ionian cities should be demoi, or "districts".
Miletus, however, received favorable terms from Cyrus. The others remained in an Ionian League of twelve cities (excluding Miletus), and were subjugated by the Persians.
Astronomy
According to Herodotus, Thales predicted the solar eclipse of 28 May 585 BC. Thales also described the position of Ursa Minor
Ursa Minor (Latin: 'Lesser Bear', contrasting with Ursa Major), also known as the Little Bear, is a constellation located in the far northern sky. As with the Great Bear, the tail of the Little Bear may also be seen as the handle of a ladle, h ...
, and he thought the constellation might be useful as a guide for navigation at sea. He calculated the duration of the year and the timings of the equinoxes
A solar equinox is a moment in time when the Sun crosses the Earth's equator, which is to say, appears directly above the equator, rather than north or south of the equator. On the day of the equinox, the Sun appears to rise "due east" and set ...
and solstices
A solstice is an event that occurs when the Sun appears to reach its most northerly or southerly excursion relative to the celestial equator on the celestial sphere. Two solstices occur annually, around June 21 and December 21. In many countri ...
. He is additionally attributed with the first observation of the Hyades Hyades may refer to:
* Hyades (band)
*Hyades (mythology)
*Hyades (star cluster)
The Hyades (; Greek Ὑάδες, also known as Caldwell 41, Collinder 50, or Melotte 25) is the nearest open cluster and one of the best-studied star clusters. Loca ...
and with calculating the position of the Pleiades
The Pleiades (), also known as The Seven Sisters, Messier 45 and other names by different cultures, is an asterism and an open star cluster containing middle-aged, hot B-type stars in the north-west of the constellation Taurus. At a distance of ...
.[ ]Plutarch
Plutarch (; grc-gre, Πλούταρχος, ''Ploútarchos''; ; – after AD 119) was a Greek Middle Platonist philosopher, historian, biographer, essayist, and priest at the Temple of Apollo in Delphi. He is known primarily for his ''P ...
indicates that in his day (c. AD 100) there was an extant work, the ''Astronomy'', composed in verse and attributed to Thales.
Herodotus
Herodotus ( ; grc, , }; BC) was an ancient Greek historian and geographer from the Greek city of Halicarnassus, part of the Persian Empire (now Bodrum, Turkey) and a later citizen of Thurii in modern Calabria ( Italy). He is known f ...
writes that in the sixth year of the war, the Lydians under King Alyattes
Alyattes (Lydian language: ; grc, Ἀλυάττης ; reigned c. 635-585 BC), sometimes described as Alyattes I, was the fourth king of the Mermnad dynasty in Lydia, the son of Sadyattes, grandson of Ardys, and great-grandson of Gyges. ...
and the Medes under Cyaxares
Cyaxares (Median: ; Old Persian: ; Akkadian: ; Old Phrygian: ; grc, Κυαξαρης, Kuaxarēs; Latin: ; reigned 625–585 BCE) was the third king of the Medes.
Cyaxares collaborated with the Babylonians to destroy the Assyrian Empire, and ...
were engaged in an indecisive battle when suddenly day turned into night, leading to both parties halting the fighting and negotiating a peace agreement. Herodotus also mentions that the loss of daylight had been predicted by Thales. He does not, however, mention the location of the battle.
However, based on the list of Median kings and the duration of their reign reported elsewhere by Herodotus, Cyaxares died 10 years before the eclipse.
Sagacity
Diogenes Laërtius
Diogenes Laërtius ( ; grc-gre, Διογένης Λαέρτιος, ; ) was a biographer of the Ancient Greece, Greek philosophers. Nothing is definitively known about his life, but his surviving ''Lives and Opinions of Eminent Philosophers'' is a ...
tells us that the Seven Sages were created in the archon
''Archon'' ( gr, ἄρχων, árchōn, plural: ἄρχοντες, ''árchontes'') is a Greek word that means "ruler", frequently used as the title of a specific public office. It is the masculine present participle of the verb stem αρχ-, mean ...
ship of Damasius at Athens
Athens ( ; el, Αθήνα, Athína ; grc, Ἀθῆναι, Athênai (pl.) ) is both the capital and largest city of Greece. With a population close to four million, it is also the seventh largest city in the European Union. Athens dominates ...
about 582 BC and that Thales was the first sage. The same story, however, asserts that Thales emigrated to Miletus
Miletus (; gr, Μῑ́λητος, Mī́lētos; Hittite transcription ''Millawanda'' or ''Milawata'' (exonyms); la, Mīlētus; tr, Milet) was an ancient Greek city on the western coast of Anatolia, near the mouth of the Maeander River in a ...
. There is also a report that he did not become a student of nature
Nature, in the broadest sense, is the physics, physical world or universe. "Nature" can refer to the phenomenon, phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. ...
until after his political career. Much as we would like to have a date on the seven sages, we must reject these stories and the tempting date if we are to believe that Thales was a native of Miletus, predicted the eclipse, and was with Croesus
Croesus ( ; Lydian: ; Phrygian: ; grc, Κροισος, Kroisos; Latin: ; reigned: c. 585 – c. 546 BC) was the king of Lydia, who reigned from 585 BC until his defeat by the Persian king Cyrus the Great in 547 or 546 BC.
Croesus was ...
in the campaign against Cyrus
Cyrus ( Persian: کوروش) is a male given name. It is the given name of a number of Persian kings. Most notably it refers to Cyrus the Great ( BC). Cyrus is also the name of Cyrus I of Anshan ( BC), King of Persia and the grandfather of Cyrus ...
.
Thales was said to have had close contacts with priests of Thebes and instructed them in geometry.
In Diogenes Laërtius' ''Lives of Eminent Philosophers'' Chapter 1.39, Laërtius relates several stories of an expensive object that is to go to the most wise. In one version (that Laërtius credits to Callimachus
Callimachus (; ) was an ancient Greek poet, scholar and librarian who was active in Alexandria during the 3rd century BC. A representative of Ancient Greek literature of the Hellenistic period, he wrote over 800 literary works in a wide variety ...
in his ''Iambics'') Bathycles of Arcadia states in his will that an expensive bowl "'should be given to him who had done most good by his wisdom.' So it was given to Thales, went the round of all the sages, and came back to Thales again. And he sent it to Apollo at Didyma, with this dedication...'Thales the Milesian, son of Examyas edicates thisto Delphinian Apollo after twice winning the prize from all the Greeks.'"
Theories
Early Greeks, and other civilizations before them, often invoked idiosyncratic
An idiosyncrasy is an unusual feature of a person (though there are also other uses, see below). It can also mean an odd habit. The term is often used to express eccentricity or peculiarity. A synonym may be "quirk".
Etymology
The term "idiosyncr ...
explanations of natural phenomena with reference to the will of anthropomorphic
Anthropomorphism is the attribution of human traits, emotions, or intentions to non-human entities. It is considered to be an innate tendency of human psychology.
Personification is the related attribution of human form and characteristics t ...
gods
A deity or god is a supernatural being who is considered divine or sacred. The ''Oxford Dictionary of English'' defines deity as a god or goddess, or anything revered as divine. C. Scott Littleton defines a deity as "a being with powers greater ...
and hero
A hero (feminine: heroine) is a real person or a main fictional character who, in the face of danger, combats adversity through feats of ingenuity, courage, or Physical strength, strength. Like other formerly gender-specific terms (like ...
es. Instead, Thales aimed to explain natural phenomena via rational hypotheses that referenced natural processes themselves. For example, rather than assuming that earthquakes were the result of supernatural whims, Thales explained them by hypothesizing that the Earth
Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...
floats on water and that earthquakes occur when the Earth is rocked by waves.
Thales was a hylozoist (one who thinks that matter is alive, i.e. containing soul(s)). Aristotle wrote (''De Anima
''On the Soul'' ( Greek: , ''Peri Psychēs''; Latin: ''De Anima'') is a major treatise written by Aristotle c. 350 BC. His discussion centres on the kinds of souls possessed by different kinds of living things, distinguished by their differen ...
'' 411 a7-8) of Thales: ...''Thales thought all things are full of gods''. Aristotle posits the origin of Thales thought on matter generally containing souls, to Thales thinking initially on the fact of, because magnets
A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, steel, nickel, ...
move iron, the presence of movement of matter indicated this matter contained life.
Thales, according to Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...
, asked what was the nature (Greek ''arche
''Arche'' (; grc, ἀρχή; sometimes also transcribed as ''arkhé'') is a Greek word with primary senses "beginning", "origin" or "source of action" (: from the beginning, οr : the original argument), and later "first principle" or "element". ...
'') of the object so that it would behave in its characteristic way. Physis
Fusis, Phusis or Physis (; grc, φύσις ) is a Greek philosophical, theological, and scientific term, usually translated into English—according to its Latin translation "natura"—as "nature". The term originated in ancient Greek philosophy ...
() comes from phyein (), "to grow", related to our word "be". ''(G)natura'' is the way a thing is "born", again with the stamp of what it is in itself.
Aristotle characterizes most of the philosophers "at first" () as thinking that the "principles in the form of matter were the only principles of all things", where "principle" is arche
''Arche'' (; grc, ἀρχή; sometimes also transcribed as ''arkhé'') is a Greek word with primary senses "beginning", "origin" or "source of action" (: from the beginning, οr : the original argument), and later "first principle" or "element". ...
, "matter" is hyle
In philosophy, hyle (; from grc, ὕλη) refers to matter or stuff. It can also be the material cause underlying a change in Aristotelian philosophy. The Greeks originally had no word for matter in general, as opposed to raw material suitable ...
("wood" or "matter", "material") and "form" is eidos
Eidos may refer to:
* Eidos (philosophy), a Greek term meaning "form" "essence", "type" or "species". See Plato's theory of forms and Aristotle's theory of universals
* Eidos plc, a British software company, which created video game publisher Eido ...
.
''Arche'' is translated as "principle", but the two words do not have precisely the same meaning. A principle
A principle is a proposition or value that is a guide for behavior or evaluation. In law, it is a Legal rule, rule that has to be or usually is to be followed. It can be desirably followed, or it can be an inevitable consequence of something, suc ...
of something is merely prior (related to pro-) to it either chronologically or logically. An arche (from , "to rule") dominates an object in some way. If the arche is taken to be an origin, then specific causality is implied; that is, B is supposed to be characteristically B just because it comes from A, which dominates it.
The archai that Aristotle had in mind in his well-known passage on the first Greek scientists are not necessarily chronologically prior to their objects, but are constituents of it. For example, in pluralism objects are composed of earth, air, fire and water, but those elements do not disappear with the production of the object. They remain as archai within it, as do the atoms of the atomists.
What Aristotle is really saying is that the first philosophers were trying to define the substance(s) of which all material objects are composed. As a matter of fact, that is exactly what modern scientists are attempting to accomplish in nuclear physics
Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter.
Nuclear physics should not be confused with atomic physics, which studies the ...
, which is a second reason why Thales is described as the first western scientist, but some contemporary scholars reject this interpretation.
Geometry
Thales was known for his theoretical and practical use of geometry
Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is c ...
, and is often considered the first person in the western world to have applied deductive reasoning to geometry (and by extension is often considered the first western mathematician). His understanding was theoretical as well as practical. For example, he said:
Thales understood similar triangles
In Euclidean geometry, two objects are similar if they have the same shape, or one has the same shape as the mirror image of the other. More precisely, one can be obtained from the other by uniformly scaling (enlarging or reducing), possibly wit ...
and right triangle
A right triangle (American English) or right-angled triangle (British), or more formally an orthogonal triangle, formerly called a rectangled triangle ( grc, ὀρθόσγωνία, lit=upright angle), is a triangle in which one angle is a right an ...
s, and what is more, used that knowledge in practical ways. The story is told in Diogenes Laërtius
Diogenes Laërtius ( ; grc-gre, Διογένης Λαέρτιος, ; ) was a biographer of the Ancient Greece, Greek philosophers. Nothing is definitively known about his life, but his surviving ''Lives and Opinions of Eminent Philosophers'' is a ...
(loc. cit.) that he measured the height of the pyramids
A pyramid (from el, πυραμίς ') is a structure whose outer surfaces are triangular and converge to a single step at the top, making the shape roughly a pyramid in the geometric sense. The base of a pyramid can be trilateral, quadrilate ...
by their shadows at the moment when his own shadow was equal to his height. A right triangle with two equal legs is a 45-degree right triangle, all of which are similar. The length of the pyramid's shadow measured from the center of the pyramid at that moment must have been equal to its height.
This story indicates that he was familiar with the Egyptian ''seked
Seked (or seqed) is an ancient Egyptian term describing the inclination of the triangular faces of a right pyramid. The system was based on the Egyptians' length measure known as the royal cubit. It was subdivided into seven ''palms'', each of wh ...
'', or ''seqed'', the ratio of the run to the rise of a slope
In mathematics, the slope or gradient of a line is a number that describes both the ''direction'' and the ''steepness'' of the line. Slope is often denoted by the letter ''m''; there is no clear answer to the question why the letter ''m'' is use ...
(cotangent
In mathematics, the trigonometric functions (also called circular functions, angle functions or goniometric functions) are real functions which relate an angle of a right-angled triangle to ratios of two side lengths. They are widely used in all ...
). The ''seked'' is at the base of problems 56, 57, 58, 59 and 60 of the Rhind papyrus
The Rhind Mathematical Papyrus (RMP; also designated as papyrus British Museum 10057 and pBM 10058) is one of the best known examples of ancient Egyptian mathematics. It is named after Alexander Henry Rhind, a Scottish antiquarian, who purchased ...
— an ancient Egyptian mathematical document.
More practically Thales used the same method to measure the distances of ships at sea, said Eudemus as reported by Proclus
Proclus Lycius (; 8 February 412 – 17 April 485), called Proclus the Successor ( grc-gre, Πρόκλος ὁ Διάδοχος, ''Próklos ho Diádokhos''), was a Greek Neoplatonist philosopher, one of the last major classical philosophers ...
("in Euclidem"). According to Kirk & Raven,[ all you need for this feat is three straight sticks pinned at one end and knowledge of your altitude. One stick goes vertically into the ground. A second is made level. With the third you sight the ship and calculate the ''seked'' from the height of the stick and its distance from the point of insertion to the line of sight (Proclus, ''In Euclidem'', 352).
]
Thales' theorems
There are two theorems of Thales in elementary geometry
Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is ca ...
, one known as Thales' theorem
In geometry, Thales's theorem states that if A, B, and C are distinct points on a circle where the line is a diameter, the angle ABC is a right angle. Thales's theorem is a special case of the inscribed angle theorem and is mentioned and proved ...
having to do with a triangle inscribed in a circle and having the circle's diameter as one leg, the other theorem being also called the intercept theorem
The intercept theorem, also known as Thales's theorem, basic proportionality theorem or side splitter theorem is an important theorem in elementary geometry about the ratios of various line segments that are created if two intersecting lines ar ...
. In addition Eudemus attributed to him the discovery that a circle is bisected by its diameter, that the base angles of an isosceles triangle are equal and that vertical angles
In Euclidean geometry, an angle is the figure formed by two rays, called the '' sides'' of the angle, sharing a common endpoint, called the ''vertex'' of the angle.
Angles formed by two rays lie in the plane that contains the rays. Angles are ...
are equal. According to a historical Note, when Thales visited Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...
, he observed that whenever the Egyptians drew two intersecting lines, they would measure the vertical angles to make sure that they were equal. Thales concluded that one could prove that all vertical angles are equal if one accepted some general notions such as: all straight angles are equal, equals added to equals are equal, and equals subtracted from equals are equal.
The evidence for the primacy of Thales comes to us from a book by Proclus
Proclus Lycius (; 8 February 412 – 17 April 485), called Proclus the Successor ( grc-gre, Πρόκλος ὁ Διάδοχος, ''Próklos ho Diádokhos''), was a Greek Neoplatonist philosopher, one of the last major classical philosophers ...
who wrote a thousand years after Thales but is believed to have had a copy of Eudemus' book. Proclus wrote "Thales was the first to go to Egypt and bring back to Greece this study." He goes on to tell us that in addition to applying the knowledge he gained in Egypt "He himself discovered many propositions and disclosed the underlying principles of many others to his successors, in some case his method being more general, in others more empirical."
Other quotes from Proclus list more of Thales' mathematical achievements:
In addition to Proclus, Hieronymus of Rhodes Hieronymus of Rhodes ( grc, Ἱερώνυμος ὁ Ῥόδιος, Hierṓnymos ho Rhódios, la, Hieronymus Rhodius; – ) was a Peripatetic philosopher, and an opponent of Arcesilaus and Lyco of Troas. Only a few fragments of his works survive, ...
also cites Thales as the first Greek mathematician. Hieronymus held that Thales was able to measure the height of the pyramids by using a theorem
In mathematics, a theorem is a statement that has been proved, or can be proved. The ''proof'' of a theorem is a logical argument that uses the inference rules of a deductive system to establish that the theorem is a logical consequence of th ...
of geometry now known as the intercept theorem
The intercept theorem, also known as Thales's theorem, basic proportionality theorem or side splitter theorem is an important theorem in elementary geometry about the ratios of various line segments that are created if two intersecting lines ar ...
, (after gathering data by using his walking-stick and comparing its shadow to those cast by the pyramids). We receive variations of Hieronymus' story through Diogenes Laërtius
Diogenes Laërtius ( ; grc-gre, Διογένης Λαέρτιος, ; ) was a biographer of the Ancient Greece, Greek philosophers. Nothing is definitively known about his life, but his surviving ''Lives and Opinions of Eminent Philosophers'' is a ...
, Pliny the Elder
Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, naturalist and natural philosopher, and naval and army commander of the early Roman Empire, and a friend of the emperor Vespasian. He wrote the encyclopedic '' ...
, and Plutarch
Plutarch (; grc-gre, Πλούταρχος, ''Ploútarchos''; ; – after AD 119) was a Greek Middle Platonist philosopher, historian, biographer, essayist, and priest at the Temple of Apollo in Delphi. He is known primarily for his ''P ...
. According to Hieronymus
Hieronymus, in English pronounced or , is the Latin form of the Ancient Greek name (Hierṓnymos), meaning "with a sacred name". It corresponds to the English given name Jerome.
Variants
* Albanian: Jeronimi
* Arabic: جيروم (Jerome)
* Basq ...
, historically quoted by Diogenes Laërtius
Diogenes Laërtius ( ; grc-gre, Διογένης Λαέρτιος, ; ) was a biographer of the Ancient Greece, Greek philosophers. Nothing is definitively known about his life, but his surviving ''Lives and Opinions of Eminent Philosophers'' is a ...
, Thales found the height of pyramids by comparison between the lengths of the shadows cast by a person and by the pyramids.
Due to the variations among testimonies, such as the "story of the sacrifice of an ox on the occasion of the discovery that the angle on a diameter of a circle is a right angle" in the version told by Diogenes Laërtius being accredited to Pythagoras rather than Thales, some historians (such as D. R. Dicks) question whether such anecdotes have any historical worth whatsoever.
Water as a first principle
Thales' most famous philosophical position was his cosmological
Cosmology () is a branch of physics and metaphysics dealing with the nature of the universe. The term ''cosmology'' was first used in English in 1656 in Thomas Blount's ''Glossographia'', and in 1731 taken up in Latin by German philosopher ...
thesis, which comes down to us through a passage from Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...
's ''Metaphysics
Metaphysics is the branch of philosophy that studies the fundamental nature of reality, the first principles of being, identity and change, space and time, causality, necessity, and possibility. It includes questions about the nature of conscio ...
''. In the work Aristotle unequivocally reported Thales' hypothesis
A hypothesis (plural hypotheses) is a proposed explanation for a phenomenon. For a hypothesis to be a scientific hypothesis, the scientific method requires that one can test it. Scientists generally base scientific hypotheses on previous obse ...
about the nature of all matter
In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic partic ...
– that the originating principle of nature was a single material substance: water. Aristotle then proceeded to proffer a number of conjectures based on his own observations to lend some credence to why Thales may have advanced this idea (though Aristotle did not hold it himself).
Aristotle laid out his own thinking about matter and form
Hylomorphism (also hylemorphism) is a philosophy, philosophical theory developed by Aristotle, which conceives every physical entity or being (''ousia'') as a compound of matter (potency) and Substantial form, immaterial form (act), with the gener ...
which may shed some light on the ideas of Thales, in ''Metaphysics
Metaphysics is the branch of philosophy that studies the fundamental nature of reality, the first principles of being, identity and change, space and time, causality, necessity, and possibility. It includes questions about the nature of conscio ...
'' 983 b6 8–11, 17–21. (The passage contains words that were later adopted by science with quite different meanings.)
In this quote we see Aristotle's depiction of the problem of change and the definition of substance. He asked if an object changes, is it the same or different? In either case how can there be a change from one to the other? The answer is that the substance "is saved", but acquires or loses different qualities (, the things you "experience").
Aristotle conjectured that Thales reached his conclusion by contemplating that the "nourishment of all things is moist and that even the hot is created from the wet and lives by it." While Aristotle's conjecture on why Thales held water as the originating principle of matter is his own thinking, his statement that Thales held it as water is generally accepted as genuinely originating with Thales and he is seen as an incipient matter-and-formist.
Thales thought the Earth must be a flat disk which is floating in an expanse of water.
Heraclitus Homericus states that Thales drew his conclusion from seeing moist substance turn into air, slime and earth. It seems likely that Thales viewed the Earth as solidifying from the water on which it floated and the oceans that surround it.
Writing centuries later, Diogenes Laërtius also states that Thales taught "Water constituted (, 'stood under') the principle of all things."
Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...
considered Thales’ position to be roughly the equivalent to the later ideas of Anaximenes, who held that everything was composed of air
The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing f ...
.
The 1870 book ''Dictionary of Greek and Roman Biography and Mythology
The ''Dictionary of Greek and Roman Biography and Mythology'' (1849, originally published 1844 under a slightly different title) is an encyclopedia/biographical dictionary. Edited by William Smith, the dictionary spans three volumes and 3,700 p ...
'' noted:
Beliefs in divinity
According to Aristotle, Thales thought lodestone
Lodestones are naturally magnetized pieces of the mineral magnetite. They are naturally occurring magnets, which can attract iron. The property of magnetism was first discovered in antiquity through lodestones. Pieces of lodestone, suspen ...
s had souls, because iron is attracted to them (by the force of magnetism
Magnetism is the class of physical attributes that are mediated by a magnetic field, which refers to the capacity to induce attractive and repulsive phenomena in other entities. Electric currents and the magnetic moments of elementary particles ...
).
Aristotle defined the soul
In many religious and philosophical traditions, there is a belief that a soul is "the immaterial aspect or essence of a human being".
Etymology
The Modern English noun ''soul'' is derived from Old English ''sāwol, sāwel''. The earliest attes ...
as the principle of life, that which imbues the matter and makes it live, giving it the animation, or power to act. The idea did not originate with him, as the Greeks in general believed in the distinction between mind and matter, which was ultimately to lead to a distinction not only between body and soul but also between matter and energy. If things were alive, they must have souls. This belief was no innovation, as the ordinary ancient populations of the Mediterranean did believe that natural actions were caused by divinities. Accordingly, Aristotle and other ancient writers state that Thales believed that "all things were full of gods."[ In their zeal to make him the first in everything some said he was the first to hold the belief, which must have been widely known to be false. However, Thales was looking for something more general, a universal substance of mind. That also was in the polytheism of the times. ]Zeus
Zeus or , , ; grc, Δῐός, ''Diós'', label=Genitive case, genitive Aeolic Greek, Boeotian Aeolic and Doric Greek#Laconian, Laconian grc-dor, Δεύς, Deús ; grc, Δέος, ''Déos'', label=Genitive case, genitive el, Δίας, ''D ...
was the very personification of supreme mind
The mind is the set of faculties responsible for all mental phenomena. Often the term is also identified with the phenomena themselves. These faculties include thought, imagination, memory, will, and sensation. They are responsible for various m ...
, dominating all the subordinate manifestations. From Thales on, however, philosophers had a tendency to depersonify or objectify mind, as though it were the substance of animation per se and not actually a god like the other gods. The result was a total removal of mind from substance, opening the door to a non-divine principle of action.
Classical thought, however, had proceeded only a little way along that path. Instead of referring to the person, Zeus, they talked about the great mind:
The universal mind appears as a Roman belief in Virgil
Publius Vergilius Maro (; traditional dates 15 October 7021 September 19 BC), usually called Virgil or Vergil ( ) in English, was an ancient Roman poet of the Augustan period. He composed three of the most famous poems in Latin literature: t ...
as well:
According to Henry Fielding
Henry Fielding (22 April 1707 – 8 October 1754) was an English novelist, irony writer, and dramatist known for earthy humour and satire. His comic novel '' Tom Jones'' is still widely appreciated. He and Samuel Richardson are seen as founders ...
(1775), Diogenes Laërtius
Diogenes Laërtius ( ; grc-gre, Διογένης Λαέρτιος, ; ) was a biographer of the Ancient Greece, Greek philosophers. Nothing is definitively known about his life, but his surviving ''Lives and Opinions of Eminent Philosophers'' is a ...
(1.35) affirmed that Thales posed "the independent pre-existence of God from all eternity, stating "that God was the oldest of all beings, for he existed without a previous cause even in the way of generation; that the world was the most beautiful of all things; for it was created by God."
Influences
Due to the scarcity of sources concerning Thales and the discrepancies between the accounts given in the sources that have survived, there is a scholarly debate over possible influences on Thales and the Greek mathematicians that came after him.
Historian Roger L. Cooke points out that Proclus
Proclus Lycius (; 8 February 412 – 17 April 485), called Proclus the Successor ( grc-gre, Πρόκλος ὁ Διάδοχος, ''Próklos ho Diádokhos''), was a Greek Neoplatonist philosopher, one of the last major classical philosophers ...
does not make any mention of Mesopotamian influence on Thales or Greek geometry, but "is shown clearly in Greek astronomy, in the use of sexagesimal system of measuring angles and in Ptolemy
Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importanc ...
's explicit use of Mesopotamian astronomical observations." Cooke notes that it may possibly also appear in the second book of Euclid's Elements
The ''Elements'' ( grc, Στοιχεῖα ''Stoikheîa'') is a mathematical treatise consisting of 13 books attributed to the ancient Greek mathematician Euclid in Alexandria, Ptolemaic Egypt 300 BC. It is a collection of definitions, postulat ...
, "which contains geometric constructions equivalent to certain algebraic relations that are frequently encountered in the cuneiform tablets." Cooke notes "This relation, however, is controversial."
Historian B.L. Van der Waerden is among those advocating the idea of Mesopotamian influence, writing "It follows that we have to abandon the traditional belief that the oldest Greek mathematicians discovered geometry entirely by themselves...a belief that was tenable only as long as nothing was known about Babylonian mathematics
Babylonian mathematics (also known as ''Assyro-Babylonian mathematics'') are the mathematics developed or practiced by the people of Mesopotamia, from the days of the early Sumerians to the centuries following the fall of Babylon in 539 BC. Babyl ...
. This in no way diminishes the stature of Thales; on the contrary, his genius receives only now the honour that is due to it, the honour of having developed a logical structure for geometry, of having introduced proof into geometry."
Some historians, such as D. R. Dicks takes issue with the idea that we can determine from the questionable sources we have, just how influenced Thales was by Babylonian sources. He points out that while Thales is held to have been able to calculate an eclipse using a cycle called the "Saros" held to have been "borrowed from the Babylonians", "The Babylonians, however, did not use cycles to predict solar eclipses, but computed them from observations of the latitude of the moon made shortly before the expected syzygy." Dicks cites historian O. Neugebauer who relates that "No Babylonian theory for predicting solar eclipse existed at 600 B.C., as one can see from the very unsatisfactory situation 400 years later; nor did the Babylonians ever develop any theory which took the influence of geographical latitude into account." Dicks examines the cycle referred to as 'Saros' – which Thales is held to have used and which is believed to stem from the Babylonians. He points out that Ptolemy makes use of this and another cycle in his book ''Mathematical Syntaxis'' but attributes it to Greek astronomers earlier than Hipparchus
Hipparchus (; el, Ἵππαρχος, ''Hipparkhos''; BC) was a Greek astronomer, geographer, and mathematician. He is considered the founder of trigonometry, but is most famous for his incidental discovery of the precession of the equi ...
and not to Babylonians. Dicks notes Herodotus does relate that Thales made use of a cycle to predict the eclipse, but maintains that "if so, the fulfillment of the 'prediction' was a stroke of pure luck not science". He goes further joining with other historians (F. Martini, J.L. E. Dreyer, O. Neugebauer) in rejecting the historicity of the eclipse story altogether. Dicks links the story of Thales discovering the cause for a solar eclipse with Herodotus' claim that Thales discovered the cycle of the sun with relation to the solstices, and concludes "he could not possibly have possessed this knowledge which neither the Egyptians nor the Babylonians nor his immediate successors possessed." Josephus is the only ancient historian that claims Thales visited Babylonia.
Herodotus wrote that the Greeks learnt the practice of dividing the day into 12 parts, about the ''polos'', and the gnomon
A gnomon (; ) is the part of a sundial that casts a shadow. The term is used for a variety of purposes in mathematics and other fields.
History
A painted stick dating from 2300 BC that was excavated at the astronomical site of Taosi is the ol ...
from the Babylonians. (The exact meaning of his use of the word ''polos'' is unknown, current theories include: "the heavenly dome", "the tip of the axis of the celestial sphere", or a spherical concave sundial.) Yet even Herodotus' claims on Babylonian influence are contested by some modern historians, such as L. Zhmud, who points out that the division of the day into twelve parts (and by analogy the year) was known to the Egyptians already in the second millennium, the gnomon was known to both Egyptians and Babylonians, and the idea of the "heavenly sphere" was not used outside of Greece at this time.
Less controversial than the position that Thales learnt Babylonian mathematics is the claim he was influenced by Egyptians. Pointedly historian S. N. Bychkov holds that the idea that the base angles of an isosceles triangle are equal likely came from Egypt. This is because, when building a roof for a home – having a cross section be exactly an isosceles triangle isn't crucial (as it's the ridge of the roof that must fit precisely), in contrast a symmetric square pyramid cannot have errors in the base angles of the faces or they will not fit together tightly.
Historian D.R. Dicks agrees that compared to the Greeks in the era of Thales, there was a more advanced state of mathematics among the Babylonians and especially the Egyptians – "both cultures knew the correct formulae for determining the areas and volumes of simple geometrical figures such as triangles, rectangles, trapezoids, etc.; the Egyptians could also calculate correctly the volume of the frustum of a pyramid with a square base (the Babylonians used an incorrect formula for this), and used a formula for the area of a circle...which gives a value for π of 3.1605—a good approximation." Dicks also agrees that this would have had an effect on Thales (whom the most ancient sources agree was interested in mathematics and astronomy) but he holds that tales of Thales' travels in these lands are pure myth.
The ancient civilization and massive monuments of Egypt had "a profound and ineradicable impression on the Greeks". They attributed to Egyptians "an immemorial knowledge of certain subjects" (including geometry) and would claim Egyptian origin for some of their own ideas to try and lend them "a respectable antiquity" (such as the "Hermetic" literature of the Alexandrian period).
Dicks holds that since Thales was a prominent figure in Greek history by the time of Eudemus but "nothing certain was known except that he lived in Miletus". A tradition developed that as "Milesians were in a position to be able to travel widely" Thales must have gone to Egypt. As Herodotus says Egypt was the birthplace of geometry he must have learnt that while there. Since he had to have been there, surely one of the theories on Nile Flooding laid out by Herodotus must have come from Thales. Likewise as he must have been in Egypt he had to have done something with the Pyramids – thus the tale of measuring them. Similar apocryphal stories exist of Pythagoras and Plato traveling to Egypt with no corroborating evidence.
As the Egyptian and Babylonian geometry at the time was "essentially arithmetic
Arithmetic () is an elementary part of mathematics that consists of the study of the properties of the traditional operations on numbers— addition, subtraction, multiplication, division, exponentiation, and extraction of roots. In the 19th ...
al", they used actual numbers and "the procedure is then described with explicit instructions as to what to do with these numbers" there was no mention of how the rules of procedure were made, and nothing toward a logically arranged corpus of generalized geometrical knowledge with analytical 'proofs' such as we find in the words of Euclid, Archimedes
Archimedes of Syracuse (;; ) was a Greek mathematician, physicist, engineer, astronomer, and inventor from the ancient city of Syracuse in Sicily. Although few details of his life are known, he is regarded as one of the leading scientists ...
, and Apollonius." So even had Thales traveled there he could not have learnt anything about the theorems he is held to have picked up there (especially because there is no evidence that any Greeks of this age could use Egyptian hieroglyphics).
Likewise until around the second century BC and the time of Hipparchus
Hipparchus (; el, Ἵππαρχος, ''Hipparkhos''; BC) was a Greek astronomer, geographer, and mathematician. He is considered the founder of trigonometry, but is most famous for his incidental discovery of the precession of the equi ...
(c. 190–120 BC) the Babylonian general division of the circle into 360 degrees and their sexagesimal system
Sexagesimal, also known as base 60 or sexagenary, is a numeral system with sixty as its base. It originated with the ancient Sumerians in the 3rd millennium BC, was passed down to the ancient Babylonians, and is still used—in a modified form ...
was unknown. Herodotus says almost nothing about Babylonian literature and science, and very little about their history. Some historians, like P. Schnabel, hold that the Greeks only learned more about Babylonian culture from Berossus
Berossus () or Berosus (; grc, Βηρωσσος, Bērōssos; possibly derived from akk, , romanized: , "Bel is his shepherd") was a Hellenistic-era Babylonian writer, a priest of Bel Marduk and astronomer who wrote in the Koine Greek language ...
, a Babylonian priest who is said to have set up a school in Cos around 270 BC (but to what extent this had in the field of geometry is contested).
Dicks points out that the primitive state of Greek mathematics and astronomical ideas exhibited by the peculiar notions of Thales' successors (such as Anaximander
Anaximander (; grc-gre, Ἀναξίμανδρος ''Anaximandros''; ) was a pre-Socratic Greek philosopher who lived in Miletus,"Anaximander" in ''Chambers's Encyclopædia''. London: George Newnes, 1961, Vol. 1, p. 403. a city of Ionia (in moder ...
, Anaximenes, Xenophanes
Xenophanes of Colophon (; grc, Ξενοφάνης ὁ Κολοφώνιος ; c. 570 – c. 478 BC) was a Greek philosopher
A philosopher is a person who practices or investigates philosophy. The term ''philosopher'' comes from the grc, φ ...
, and Heraclitus
Heraclitus of Ephesus (; grc-gre, Ἡράκλειτος , "Glory of Hera"; ) was an ancient Greek pre-Socratic philosopher from the city of Ephesus, which was then part of the Persian Empire.
Little is known of Heraclitus's life. He wrote ...
), which historian J. L. Heiberg calls "a mixture of brilliant intuition and childlike analogies", argues against the assertions from writers in late antiquity that Thales discovered and taught advanced concepts in these fields.
John Burnet (1892) noted
According to the 10th-century Byzantine encyclopedia ''Suda
The ''Suda'' or ''Souda'' (; grc-x-medieval, Σοῦδα, Soûda; la, Suidae Lexicon) is a large 10th-century Byzantine encyclopedia of the ancient Mediterranean world, formerly attributed to an author called Soudas (Σούδας) or Souidas ...
'', Thales had been the "teacher and kineman" of Anaximander.
Nicholas Molinari has recently argued for an important Greek influence on Thales' idea of the ''archai'', namely, the archaic water deity Acheloios, who was equated with water and worshipped in Miletos during Thales' life. He argues that Thales, as a sage and world traveler, was exposed to many mythologies and religions, and while they all had some influence, his hometown Acheloios was the most essential. For evidence, he points to the fact that ''hydor'' meant specifically "fresh water," and that Acheloios was seen as a shape-shifter in myth and art, so able to become anything. He also points out that the rivers of the world were seen as the "sinews of Acheloios" in antiquity, and this multiplicity of deities is reflected in Thales' idea that "all things are full of gods."
Interpretations
In the long sojourn of philosophy, there has existed hardly a philosopher or historian of philosophy who did not mention Thales and try to characterize him in some way. He is generally recognized as having brought something new to human thought. Mathematics, astronomy, and medicine already existed. Thales added something to these different collections of knowledge to produce a universality, which, as far as writing tells us, was not in tradition before, but resulted in a new field.
Ever since, interested persons have been asking what that new something is. Answers fall into (at least) two categories, the theory and the method. Once an answer has been arrived at, the next logical step is to ask how Thales compares to other philosophers, which leads to his classification (rightly or wrongly).
Theory
The most natural epithets of Thales are "materialist
Materialism is a form of philosophical monism which holds matter to be the fundamental substance in nature, and all things, including mental states and consciousness, are results of material interactions. According to philosophical materialis ...
" and " naturalist", which are based on ousia and physis. The Catholic Encyclopedia
The ''Catholic Encyclopedia: An International Work of Reference on the Constitution, Doctrine, Discipline, and History of the Catholic Church'' (also referred to as the ''Old Catholic Encyclopedia'' and the ''Original Catholic Encyclopedia'') i ...
notes that Aristotle called him a physiologist, with the meaning "student of nature." On the other hand, he would have qualified as an early physicist
A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe.
Physicists generally are interested in the root or ultimate caus ...
, as did Aristotle. They studied corpora, "bodies", the medieval descendants of substances.
Russell
Most agree that Thales' stamp on thought is the unity of substance, hence Bertrand Russell
Bertrand Arthur William Russell, 3rd Earl Russell, (18 May 1872 – 2 February 1970) was a British mathematician, philosopher, logician, and public intellectual. He had a considerable influence on mathematics, logic, set theory, linguistics, ...
:
Russell was only reflecting an established tradition; for example: Nietzsche
Friedrich Wilhelm Nietzsche (; or ; 15 October 1844 – 25 August 1900) was a German philosopher, Prose poetry, prose poet, cultural critic, Philology, philologist, and composer whose work has exerted a profound influence on contemporary philo ...
, in his ''Philosophy in the Tragic Age of the Greeks
''Philosophy in the Tragic Age of the Greeks'' (german: Philosophie im tragischen Zeitalter der Griechen) is an incomplete book by Friedrich Nietzsche. He had a clean copy made from his notes with the intention of publication. The notes were writ ...
'', wrote:
This sort of materialism, however, should not be confused with deterministic materialism. Thales was only trying to explain the unity observed in the free play of the qualities. The arrival of uncertainty in the modern world made possible a return to Thales; for example, John Elof Boodin John Elof Boodin (November 14, 1869 – November 14, 1950) was a Swedish-born American philosopher and educator. He was the author of numerous books proposing a systematic interpretation of nature. Boodin's work preserved the tradition of philosop ...
writes ("God and Creation"):
Boodin
Boodin defines an "emergent" materialism, in which the objects of sense emerge uncertainly from the substrate. Thales is the innovator of this sort of materialism.
Feldman
Later scholastic thinkers would maintain that in his choice of water Thales was influenced by Babylonian or Chaldean religion, that held that a god had begun creation by acting upon the pre-existing water. Historian Abraham Feldman holds this does not stand up under closer examination. In Babylonian religion the water is lifeless and sterile until a god acts upon it, but for Thales water itself was divine and creative. He maintained that "All things are full of gods", and to understand the nature of things was to discover the secrets of the deities, and through this knowledge open the possibility that one could be greater than the grandest Olympian.
Feldman points out that while other thinkers recognized the wetness of the world "none of them was inspired to conclude that everything was ultimately aquatic." He further points out that Thales was "a wealthy citizen of the fabulously rich Oriental port of Miletus...a dealer in the staples of antiquity, wine and oil...He certainly handled the shell-fish of the Phoenicians that secreted the dye of imperial purple." Feldman recalls the stories of Thales measuring the distance of boats in the harbor, creating mechanical improvements for ship navigation, giving an explanation for the flooding of the Nile
The flooding of the Nile has been an important natural cycle in Egypt since Ancient Egypt, ancient times. It is celebrated by Egyptians as an annual holiday for two weeks starting August 15, known as ''Wafaa El-Nil''. It is also celebrated in the ...
(vital to Egyptian agriculture and Greek trade), and changing the course of the river Halys so an army could ford it. Rather than seeing water as a barrier Thales contemplated the Ionian yearly religious gathering for athletic ritual (held on the promontory of Mycale and believed to be ordained by the ancestral kindred of Poseidon, the god of the sea). He called for the Ionian mercantile states participating in this ritual to convert it into a democratic federation under the protection of Poseidon that would hold off the forces of pastoral Persia. Feldman concludes that Thales saw "that water was a revolutionary leveler and the elemental factor determining the subsistence and business of the world" and "the common channel of states."
Feldman considers Thales' environment and holds that Thales would have seen tears, sweat, and blood as granting value to a person's work and the means how life giving commodities travelled (whether on bodies of water or through the sweat of slaves and pack-animals). He would have seen that minerals could be processed from water such as life-sustaining salt and gold taken from rivers. He would’ve seen fish and other food stuffs gathered from it. Feldman points out that Thales held that the lodestone
Lodestones are naturally magnetized pieces of the mineral magnetite. They are naturally occurring magnets, which can attract iron. The property of magnetism was first discovered in antiquity through lodestones. Pieces of lodestone, suspen ...
was alive as it drew metals to itself. He holds that Thales "living ever in sight of his beloved sea" would see water seem to draw all "traffic in wine and oil, milk and honey, juices and dyes" to itself, leading him to "a vision of the universe melting into a single substance that was valueless in itself and still the source of wealth." Feldman concludes that for Thales "...water united all things. The social significance of water in the time of Thales induced him to discern through hardware and dry-goods, through soil and sperm, blood, sweat and tears, one fundamental fluid stuff...water, the most commonplace and powerful material known to him." This combined with his contemporary's idea of "spontaneous generation
Spontaneous generation is a superseded scientific theory that held that living creatures could arise from nonliving matter and that such processes were commonplace and regular. It was hypothesized that certain forms, such as fleas, could arise fr ...
" allow us to see how Thales could hold that water could be divine and creative.
Feldman points to the lasting association of the theory that "all whatness is wetness" with Thales himself, pointing out that Diogenes Laërtius speaks of a poem, probably a satire, where Thales is snatched to heaven by the sun.
Rise of theoretical inquiry
In the West, Thales represents a new kind of inquiring community as well. Edmund Husserl
, thesis1_title = Beiträge zur Variationsrechnung (Contributions to the Calculus of Variations)
, thesis1_url = https://fedora.phaidra.univie.ac.at/fedora/get/o:58535/bdef:Book/view
, thesis1_year = 1883
, thesis2_title ...
attempts to capture the new movement as follows. Philosophical man is a "new cultural configuration" based in stepping back from "pregiven tradition" and taking up a rational "inquiry into what is true in itself;" that is, an ideal of truth. It begins with isolated individuals such as Thales, but they are supported and cooperated with as time goes on. Finally the ideal transforms the norms of society, leaping across national borders.
Classification
The term "Pre-Socratic
Pre-Socratic philosophy, also known as early Greek philosophy, is ancient Greek philosophy before Socrates. Pre-Socratic philosophers were mostly interested in cosmology, the beginning and the substance of the universe, but the inquiries of thes ...
" derives ultimately from the philosopher Aristotle, who distinguished the early philosophers as concerning themselves with substance.
Diogenes Laërtius on the other hand took a strictly geographic and ethnic approach. Philosophers were either Ionian or Italian. He used "Ionian" in a broader sense, including also the Athenian academics, who were not Pre-Socratics. From a philosophic point of view, any grouping at all would have been just as effective. There is no basis for an Ionian or Italian unity. Some scholars, however, concede to Diogenes' scheme as far as referring to an "Ionian" school. There was no such school in any sense.
The most popular approach refers to a Milesian school, which is more justifiable socially and philosophically. They sought for the substance of phenomena and may have studied with each other. Some ancient writers qualify them as Milesioi, "of Miletus."
Influence on others
Thales had a profound influence on other Greek thinkers and therefore on Western
Western may refer to:
Places
*Western, Nebraska, a village in the US
*Western, New York, a town in the US
*Western Creek, Tasmania, a locality in Australia
*Western Junction, Tasmania, a locality in Australia
*Western world, countries that id ...
history. Some believe Anaximander
Anaximander (; grc-gre, Ἀναξίμανδρος ''Anaximandros''; ) was a pre-Socratic Greek philosopher who lived in Miletus,"Anaximander" in ''Chambers's Encyclopædia''. London: George Newnes, 1961, Vol. 1, p. 403. a city of Ionia (in moder ...
was a pupil of Thales. Early sources report that one of Anaximander's more famous pupils, Pythagoras
Pythagoras of Samos ( grc, Πυθαγόρας ὁ Σάμιος, Pythagóras ho Sámios, Pythagoras the Samos, Samian, or simply ; in Ionian Greek; ) was an ancient Ionians, Ionian Ancient Greek philosophy, Greek philosopher and the eponymou ...
, visited Thales as a young man, and that Thales advised him to travel to Egypt to further his philosophical and mathematical studies.
Many philosophers followed Thales' lead in searching for explanations in nature
Nature, in the broadest sense, is the physics, physical world or universe. "Nature" can refer to the phenomenon, phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. ...
rather than in the supernatural; others returned to supernatural explanations, but couched them in the language of philosophy rather than of myth or of religion
Religion is usually defined as a social- cultural system of designated behaviors and practices, morals, beliefs, worldviews, texts, sanctified places, prophecies, ethics, or organizations, that generally relates humanity to supernatural, ...
.
Looking specifically at Thales' influence during the pre-Socratic era, it is clear that he stood out as one of the first thinkers who thought more in the way of ''logos
''Logos'' (, ; grc, wikt:λόγος, λόγος, lógos, lit=word, discourse, or reason) is a term used in Western philosophy, psychology and rhetoric and refers to the appeal to reason that relies on logic or reason, inductive and deductive ...
'' than ''mythos
Myth is a folklore genre consisting of narratives that play a fundamental role in a society, such as foundational tales or origin myths. Since "myth" is widely used to imply that a story is not objectively true, the identification of a narrati ...
''. The difference between these two more profound ways of seeing the world is that ''mythos'' is concentrated around the stories of holy origin, while ''logos'' is concentrated around the argumentation. When the mythical man wants to explain the world the way he sees it, he explains it based on gods and powers. Mythical thought does not differentiate between things and persons and furthermore it does not differentiate between nature and culture. The way a ''logos'' thinker would present a world view is radically different from the way of the mythical thinker. In its concrete form, ''logos'' is a way of thinking not only about individualism, but also the abstract. Furthermore, it focuses on sensible and continuous argumentation. This lays the foundation of philosophy
Philosophy (from , ) is the systematized study of general and fundamental questions, such as those about existence, reason, knowledge, values, mind, and language. Such questions are often posed as problems to be studied or resolved. Some ...
and its way of explaining the world in terms of abstract argumentation, and not in the way of gods and mythical stories.
Reliability of sources
Because of Thales' elevated status in Greek culture, an intense interest and admiration followed his reputation. Due to this following, the oral stories about his life were open to amplification and historical fabrication, even before they were written down generations later. Most modern dissension comes from trying to interpret what we know, in particular, distinguishing legend from fact.
Chronological classification
Historian D.R. Dicks and other historians divide the ancient sources about Thales into those before 320 BC and those after that year (including some such as Proclus
Proclus Lycius (; 8 February 412 – 17 April 485), called Proclus the Successor ( grc-gre, Πρόκλος ὁ Διάδοχος, ''Próklos ho Diádokhos''), was a Greek Neoplatonist philosopher, one of the last major classical philosophers ...
writing in the 5th century C.E. and Simplicius of Cilicia
Simplicius of Cilicia (; el, Σιμπλίκιος ὁ Κίλιξ; c. 490 – c. 560 AD) was a disciple of Ammonius Hermiae and Damascius, and was one of the last of the Neoplatonists. He was among the pagan philosophers persecuted by Justinian i ...
in the 6th century C.E., who wrote nearly a millennium after his era). The first category includes Herodotus
Herodotus ( ; grc, , }; BC) was an ancient Greek historian and geographer from the Greek city of Halicarnassus, part of the Persian Empire (now Bodrum, Turkey) and a later citizen of Thurii in modern Calabria ( Italy). He is known f ...
, Plato
Plato ( ; grc-gre, Πλάτων ; 428/427 or 424/423 – 348/347 BC) was a Greek philosopher born in Athens during the Classical period in Ancient Greece. He founded the Platonist school of thought and the Academy, the first institution ...
, Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...
, Aristophanes
Aristophanes (; grc, Ἀριστοφάνης, ; c. 446 – c. 386 BC), son of Philippus, of the deme
In Ancient Greece, a deme or ( grc, δῆμος, plural: demoi, δημοι) was a suburb or a subdivision of Athens and other city-states ...
, and Theophrastus
Theophrastus (; grc-gre, Θεόφραστος ; c. 371c. 287 BC), a Greek philosopher and the successor to Aristotle in the Peripatetic school. He was a native of Eresos in Lesbos.Gavin Hardy and Laurence Totelin, ''Ancient Botany'', Routledge ...
among others. The second category includes Plautus
Titus Maccius Plautus (; c. 254 – 184 BC), commonly known as Plautus, was a Roman playwright of the Old Latin period. His comedies are the earliest Latin literary works to have survived in their entirety. He wrote Palliata comoedia, the gen ...
, Aetius, Eusebius
Eusebius of Caesarea (; grc-gre, Εὐσέβιος ; 260/265 – 30 May 339), also known as Eusebius Pamphilus (from the grc-gre, Εὐσέβιος τοῦ Παμφίλου), was a Greek historian of Christianity, exegete, and Christian ...
, Plutarch
Plutarch (; grc-gre, Πλούταρχος, ''Ploútarchos''; ; – after AD 119) was a Greek Middle Platonist philosopher, historian, biographer, essayist, and priest at the Temple of Apollo in Delphi. He is known primarily for his ''P ...
, Josephus
Flavius Josephus (; grc-gre, Ἰώσηπος, ; 37 – 100) was a first-century Romano-Jewish historian and military leader, best known for ''The Jewish War'', who was born in Jerusalem—then part of Roman Judea—to a father of priestly d ...
, Iamblichus
Iamblichus (; grc-gre, Ἰάμβλιχος ; Aramaic: 𐡉𐡌𐡋𐡊𐡅 ''Yamlīḵū''; ) was a Syrian neoplatonic philosopher of Arabic origin. He determined a direction later taken by neoplatonism. Iamblichus was also the biographer of ...
, Diogenes Laërtius
Diogenes Laërtius ( ; grc-gre, Διογένης Λαέρτιος, ; ) was a biographer of the Ancient Greece, Greek philosophers. Nothing is definitively known about his life, but his surviving ''Lives and Opinions of Eminent Philosophers'' is a ...
, Theon of Smyrna
Theon of Smyrna ( el, Θέων ὁ Σμυρναῖος ''Theon ho Smyrnaios'', ''gen.'' Θέωνος ''Theonos''; fl. 100 CE) was a Greek philosopher and mathematician, whose works were strongly influenced by the Pythagorean school of thought. His ...
, Apuleius
Apuleius (; also called Lucius Apuleius Madaurensis; c. 124 – after 170) was a Numidian Latin-language prose writer, Platonist philosopher and rhetorician. He lived in the Roman province of Numidia, in the Berber city of Madauros, modern-day ...
, Clement of Alexandria
Titus Flavius Clemens, also known as Clement of Alexandria ( grc , Κλήμης ὁ Ἀλεξανδρεύς; – ), was a Christian theologian and philosopher who taught at the Catechetical School of Alexandria. Among his pupils were Origen and ...
, Pliny the Elder
Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, naturalist and natural philosopher, and naval and army commander of the early Roman Empire, and a friend of the emperor Vespasian. He wrote the encyclopedic '' ...
, and John Tzetzes
John Tzetzes ( grc-gre, Ἰωάννης Τζέτζης, Iōánnēs Tzétzēs; c. 1110, Constantinople – 1180, Constantinople) was a Byzantine poet and grammarian who is known to have lived at Constantinople in the 12th century.
He was able to p ...
among others.
Earliest sources
The earliest sources on Thales (living before 320 BC) are often the same for the other Milesian philosophers (Anaximander
Anaximander (; grc-gre, Ἀναξίμανδρος ''Anaximandros''; ) was a pre-Socratic Greek philosopher who lived in Miletus,"Anaximander" in ''Chambers's Encyclopædia''. London: George Newnes, 1961, Vol. 1, p. 403. a city of Ionia (in moder ...
, and Anaximenes). These sources were either roughly contemporaneous (such as Herodotus
Herodotus ( ; grc, , }; BC) was an ancient Greek historian and geographer from the Greek city of Halicarnassus, part of the Persian Empire (now Bodrum, Turkey) and a later citizen of Thurii in modern Calabria ( Italy). He is known f ...
) or lived within a few hundred years of his passing. Moreover, they were writing from an oral tradition that was widespread and well known in the Greece of their day.
Latter sources
The latter sources on Thales are several "ascriptions of commentators and compilers who lived anything from 700 to 1,000 years after his death" which include "anecdotes of varying degrees of plausibility" and in the opinion of some historians (such as D. R. Dicks) of "no historical worth whatsoever". Dicks points out that there is no agreement "among the 'authorities' even on the most fundamental facts of his life—e.g. whether he was a Milesian or a Phoenician, whether he left any writings or not, whether he was married or single—much less on the actual ideas and achievements with which he is credited."
Comparison of the two source groups
Contrasting the work of the more ancient writers with those of the later, Dicks points out that in the works of the early writers Thales and the other men who would be hailed as "the Seven Sages of Greece" had a different reputation than that which would be assigned to them by later authors. Closer to their own era, Thales, Solon
Solon ( grc-gre, Σόλων; BC) was an Athenian statesman, constitutional lawmaker and poet. He is remembered particularly for his efforts to legislate against political, economic and moral decline in Archaic Athens.Aristotle ''Politics'' ...
, Bias of Priene
Bias (; Greek: Βίας ὁ Πριηνεύς; fl. 6th century BC) of Priene was a Greek sage. He is widely accepted as one of the Seven Sages of Greece and was renowned for his probity.
Life
Bias was born at Priene (modern-day Güllübahçe, Tur ...
, Pittacus of Mytilene
Pittacus (; grc-gre, Πιττακός; 640 – 568 BC) was an ancient Mytilenean military general and one of the Seven Sages of Greece.
Biography
Pittacus was a native of Mytilene and son of Hyrradius. He became a Mytilenaean general who, with ...
and others were hailed as "essentially practical men who played leading roles in the affairs of their respective states, and were far better known to the earlier Greeks as lawgivers and statesmen than as profound thinkers and philosophers." For example, Plato praises him (coupled with Anacharsis
Anacharsis (; grc, Ἀνάχαρσις) was a Scythian philosopher; he travelled from his homeland on the northern shores of the Black Sea, to Ancient Athens, in the early 6th century BC, and made a great impression as a forthright and outspok ...
) for being the originator of the potter's wheel and the anchor.
Only in the writings of the second group of writers (working after 320 BC) do "we obtain the picture of Thales as the pioneer in Greek scientific thinking, particularly in regard to mathematics and astronomy which he is supposed to have learnt about in Babylonia and Egypt." Rather than "the earlier tradition here
Here is an adverb that means "in, on, or at this place". It may also refer to:
Software
* Here Technologies, a mapping company
* Here WeGo (formerly Here Maps), a mobile app and map website by Here Technologies, Here
Television
* Here TV (form ...
he is a favourite example of the intelligent man who possesses some technical 'know how'...the later doxographers uch_as_Dicaearchus_in_the_latter_half_of_the_fourth_century_BC.html" ;"title="Dicaearchus.html" ;"title="uch as Dicaearchus">uch as Dicaearchus in the latter half of the fourth century BC">Dicaearchus.html" ;"title="uch as Dicaearchus">uch as Dicaearchus in the latter half of the fourth century BCfoist on to him any number of discoveries and achievements, in order to build him up as a figure of superhuman wisdom."
Problem suggested by Dicks
Dicks points out a further problem arises in the surviving information on Thales, for rather than using ancient sources closer to the era of Thales, the authors in later antiquity ("epitomators, excerptors, and compilers") actually "preferred to use one or more intermediaries, so that what we actually read in them comes to us not even at second, but at third or fourth or fifth hand. Obviously, this use of intermediate sources, copied and recopied from century to century, with each writer adding additional pieces of information of greater or less plausibility from his own knowledge, provided a fertile field for errors in transmission, wrong ascriptions, and fictitious attributions". Dicks points out that "certain doctrines that later commentators invented for Thales...were then accepted into the biographical tradition" being copied by subsequent writers who were then cited by those coming after them "and thus, because they may be repeated by different authors relying on different sources, may produce an illusory impression of genuineness."
Aristotle
Doubts even exist when considering the philosophical positions held to originate in Thales "in reality these stem directly from Aristotle's own interpretations which then became incorporated in the doxographical tradition as erroneous ascriptions to Thales". (The same treatment was given by Aristotle to Anaxagoras.)
Most philosophic analyses of the philosophy of Thales come from Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...
, a professional philosopher, tutor of Alexander the Great
Alexander III of Macedon ( grc, wikt:Ἀλέξανδρος, Ἀλέξανδρος, Alexandros; 20/21 July 356 BC – 10/11 June 323 BC), commonly known as Alexander the Great, was a king of the Ancient Greece, ancient Greek kingdom of Maced ...
, who wrote 200 years after Thales' death. Aristotle, judging from his surviving books, does not seem to have access to any works by Thales, although he probably had access to works of other authors about Thales, such as Herodotus
Herodotus ( ; grc, , }; BC) was an ancient Greek historian and geographer from the Greek city of Halicarnassus, part of the Persian Empire (now Bodrum, Turkey) and a later citizen of Thurii in modern Calabria ( Italy). He is known f ...
, Hecataeus, Plato
Plato ( ; grc-gre, Πλάτων ; 428/427 or 424/423 – 348/347 BC) was a Greek philosopher born in Athens during the Classical period in Ancient Greece. He founded the Platonist school of thought and the Academy, the first institution ...
etc., as well as others whose work is now extinct. It was Aristotle's express goal to present Thales' work not because it was significant in itself, but as a prelude to his own work in natural philosophy. Geoffrey Kirk
Geoffrey Stephen Kirk, () was a British classicist who served as the 35th Regius Professor of Greek at the University of Cambridge. He published widely on pre-Socratic philosophy and the work of the Greek poet Homer, culminating in a six-volu ...
and John Raven
John Earle Raven (13 December 1914 – 5 March 1980) was an English classical scholar, notable for his work on presocratic philosophy, and amateur botanist.
Early life and education
John Raven was born on 13 December 1914 in Cambridge, the son ...
, English compilers of the fragments of the Pre-Socratics, assert that Aristotle's "judgments are often distorted by his view of earlier philosophy as a stumbling progress toward the truth that Aristotle himself revealed in his physical doctrines."[ There was also an extensive oral tradition. Both the oral and the written were commonly read or known by all educated men in the region.
Aristotle's philosophy had a distinct stamp: it professed the theory of matter and form, which modern scholastics have dubbed ]hylomorphism
Hylomorphism (also hylemorphism) is a philosophical theory developed by Aristotle, which conceives every physical entity or being (''ousia'') as a compound of matter (potency) and immaterial form (act), with the generic form as immanently real ...
. Though once very widespread, it was not generally adopted by rationalist and modern science, as it mainly is useful in metaphysical
Metaphysics is the branch of philosophy that studies the fundamental nature of reality, the first principles of being, identity and change, space and time, causality, necessity, and possibility. It includes questions about the nature of conscio ...
analyses, but does not lend itself to the detail that is of interest to modern science. It is not clear that the theory of matter and form existed as early as Thales, and if it did, whether Thales espoused it.
While some historians, like B. Snell, maintain that Aristotle was relying on a pre-Platonic written record by Hippias
Hippias of Elis (; el, Ἱππίας ὁ Ἠλεῖος; late 5th century BC) was a Greek sophist, and a contemporary of Socrates. With an assurance characteristic of the later sophists, he claimed to be regarded as an authority on all subjects ...
rather than oral tradition, this is a controversial position. Representing the scholarly consensus Dicks states that "the tradition about him even as early as the fifth century B.C., was evidently based entirely on hearsay....It would seem that already by Aristotle's time the early Ionians were largely names only to which popular tradition attached various ideas or achievements with greater or less plausibility". He points out that works confirmed to have existed in the sixth century BC by Anaximander and Xenophanes had already disappeared by the fourth century BC, so the chances of Pre-Socratic material surviving to the age of Aristotle is almost nil (even less likely for Aristotle's pupils Theophrastus and Eudemus and less likely still for those following after them).
Diogenes Laërtius
The main secondary source concerning the details of Thales' life and career is Diogenes Laërtius
Diogenes Laërtius ( ; grc-gre, Διογένης Λαέρτιος, ; ) was a biographer of the Ancient Greece, Greek philosophers. Nothing is definitively known about his life, but his surviving ''Lives and Opinions of Eminent Philosophers'' is a ...
, "'' Lives of Eminent Philosophers''". This is primarily a biographical work, as the name indicates. Compared to Aristotle, Diogenes is not much of a philosopher. He is the one who, in the Prologue to that work, is responsible for the division of the early philosophers into "Ionian" and "Italian", but he places the Academics in the Ionian school and otherwise evidences considerable disarray and contradiction, especially in the long section on forerunners of the "Ionian School". Diogenes quotes two letters attributed to Thales, but Diogenes wrote some eight centuries after Thales' death and that his sources often contained "unreliable or even fabricated information", hence the concern for separating fact from legend in accounts of Thales.
It is due to this use of hearsay and a lack of citing original sources that leads some historians, like Dicks and Werner Jaeger, to look at the late origin of the traditional picture of Pre-Socratic philosophy and view the whole idea as a construct from a later age, "the whole picture that has come down to us of the history of early philosophy was fashioned during the two or three generations from Plato to the immediate pupils of Aristotle".
See also
* Know thyself
The Ancient Greek aphorism "know thyself" (Greek: , transliterated: '; also ' with the ε contracted) is the first of three Delphic maxims inscribed in the forecourt of the Temple of Apollo at Delphi according to the Greek writer Pausania ...
* Material monism
Material monism is a Pre-Socratic belief which provides an explanation of the physical world by saying that all of the world's objects are composed of a single element.
Among the material monists were the three Milesian philosophers: Thales, who ...
* Plato's Academy mosaic
Plato's Academy mosaic is a work of visual art created in the villa of T. Siminius Stephanus in Pompeii, around 100 BC to 79 AD. Of mosaic construction, it has roughly square dimensions, and is about the size of a large dinner plate.
It depic ...
Notes
References
* (1991 pbk ed.
2011 3rd edition
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* Herodotus
Herodotus ( ; grc, , }; BC) was an ancient Greek historian and geographer from the Greek city of Halicarnassus, part of the Persian Empire (now Bodrum, Turkey) and a later citizen of Thurii in modern Calabria ( Italy). He is known f ...
, '' Histories'', A. D. Godley
Alfred Denis Godley (22 January 1856 – 27 June 1925) was an Anglo-Irish classical scholar and author of humorous poems. From 1910 to 1920 he was Public Orator at the University of Oxford, a post that involved composing citations in Latin for ...
(translator), Cambridge: Harvard University Press, 1920;
Online version at Perseus
* Hans Joachim Störig, ''Kleine Weltgeschichte der Philosophie''. Fischer, Frankfurt/M. 2004, .
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* Pliny the Elder
Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, naturalist and natural philosopher, and naval and army commander of the early Roman Empire, and a friend of the emperor Vespasian. He wrote the encyclopedic '' ...
, '' The Natural History'' (eds. John Bostock, M.D., F.R.S. H.T. Riley, Esq., B.A.) London. Taylor and Francis. (1855)
Online version
at the Perseus Digital Library.
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Further reading
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* Priou, Alex (2016).
The Origin and Foundations of Milesian Thought
" ''The Review of Metaphysics'' 70, 3–31.
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External links
* ttps://mathshistory.st-andrews.ac.uk/Biographies/Thales/ Thales of MiletusMacTutor History of Mathematics
Thales' Theorem – Math Open Reference
(with interactive animation)
(with extensive bibliography)
Life, Work and Testimonies by Giannis Stamatellos
Thales Fragments
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6th-century BC Greek people
6th-century BC philosophers
620s BC births
540s BC deaths
Ancient Greek astronomers
Ancient Greek geometers
Ancient Greek metaphysicians
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Ancient Milesians
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Founders of philosophical traditions
Metaphilosophers
Metaphysicians
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Philosophers of ancient Ionia
Philosophers of education
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Presocratic philosophers
Seven Sages of Greece
6th-century BC mathematicians