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 ...
, extension signifies both 'stretching out' (Latin: ''extensio'') as well as later 'taking up space', and most recently, spreading one's internal mental cognition into the external world.
The history of thinking about ''extension'' can be traced back at least to
Archytas
Archytas (; el, Ἀρχύτας; 435/410–360/350 BC) was an Ancient Greek philosopher, mathematician, music theorist, astronomer, statesman, and strategist. He was a scientist of the Pythagorean school and famous for being the reputed founder ...
' spear analogy for the infinity of space. How far can one's hand or spear stretch out until it reaches the edge of reality? “If I arrived at the outermost edge of the heaven, could I extend my hand or staff into what is outside or not? It would be paradoxical
iven our normal assumptions about the nature of space
Iven is a Municipalities of Germany, municipality in the Vorpommern-Greifswald district, in Mecklenburg-Vorpommern, Germany.
Notable residents
*Georg Detlev von Flemming (1699–1771), Saxon-Polish general
References
Vorpommern-Greifsw ...
not to be able to extend it.”
History
Descartes
René Descartes
René Descartes ( or ; ; Latinized: Renatus Cartesius; 31 March 1596 – 11 February 1650) was a French philosopher, scientist, and mathematician, widely considered a seminal figure in the emergence of modern philosophy and science. Mathem ...
defined extension as the property of existing in more than one dimension, a property that was later followed up in Grassmann's n-dimensional algebra. For Descartes, the primary characteristic 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 ...
is extension (''res extensa''), just as the primary characteristic of
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 ...
is
thought
In their most common sense, the terms thought and thinking refer to conscious cognitive processes that can happen independently of sensory stimulation. Their most paradigmatic forms are judging, reasoning, concept formation, problem solving, a ...
(''res cogitans'').
Newton
After rejecting Cartesian identification of body with extension ,
Newton
Newton most commonly refers to:
* Isaac Newton (1642–1726/1727), English scientist
* Newton (unit), SI unit of force named after Isaac Newton
Newton may also refer to:
Arts and entertainment
* ''Newton'' (film), a 2017 Indian film
* Newton ( ...
turns to the question of what the nature of the "immobile being"—space or extension itself, distinguished from body—was. He raises three possible definitions for extension: as a kind of ''substance''; or as a kind of ''accident'' (a standard philosophical term for ''attribute'': anything that can be predicated of substance); or "''simply nothing''" (a reference to atomism), all of which he repudiates. Instead he proposes that extension "has a certain mode of existence of its own, which agrees neither with substances nor accidents."
After struggling with this question, Newton provides perhaps one of the clearest definitions of extension
which lead Stein to conclude Newton's conception of Space, the existence of space, or extension, ''follows from'' that of anything whatsoever; but extension does not require a subject in which it "inheres", as a property; and it can be conceived as existent without presupposing any ''particular'' thing, God included. On the other hand, it is an "affection of every being."
[
]
Locke
John Locke
John Locke (; 29 August 1632 – 28 October 1704) was an English philosopher and physician, widely regarded as one of the most influential of Age of Enlightenment, Enlightenment thinkers and commonly known as the "father of liberalism ...
, in ''An Essay Concerning Human Understanding
''An Essay Concerning Human Understanding'' is a work by John Locke concerning the foundation of human knowledge and understanding. It first appeared in 1689 (although dated 1690) with the printed title ''An Essay Concerning Humane Understand ...
'', defined extension as "only the Space that lies between the Extremities of those solid coherent Parts" of a body. It is the space possessed by a body. Locke refers to the extension in conjunction with ''solidity
Solidity is an object-oriented programming language for implementing smart contracts on various blockchain platforms, most notably, Ethereum. It was developed by Christian Reitwiessner, Alex Beregszaszi, and several former Ethereum core contri ...
'' and ''impenetrability In metaphysics, impenetrability is the name given to that quality of matter whereby two bodies cannot occupy the same space at the same time. The philosopher John Toland argued that impenetrability and extension (metaphysics), extension were suffici ...
,'' the other primary characteristics of matter.
Extension also plays an important part in the philosophy of Baruch Spinoza
Baruch (de) Spinoza (born Bento de Espinosa; later as an author and a correspondent ''Benedictus de Spinoza'', anglicized to ''Benedict de Spinoza''; 24 November 1632 – 21 February 1677) was a Dutch philosopher of Portuguese-Jewish origin, b ...
, who says that substance (that which has extension) can be limited only by substance of the same sort, i.e. matter cannot be limited by ideas and vice versa. From this principle, he determines that substance is infinite. This infinite substance is what Spinoza calls God
In monotheism, monotheistic thought, God is usually viewed as the supreme being, creator deity, creator, and principal object of Faith#Religious views, faith.Richard Swinburne, Swinburne, R.G. "God" in Ted Honderich, Honderich, Ted. (ed)''The Ox ...
, or better yet 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 it possesses both unlimited extension and unlimited consciousness.
Infinite divisibility
''Infinite divisibility'' refers to the idea that extension, or quantity, when divided and further divided infinitely, cannot reach the point of zero quantity. It can be divided into very small or negligible quantity but not zero or no quantity at all. Using a mathematical approach, specifically geometric models, Gottfried Leibniz
Gottfried Wilhelm (von) Leibniz . ( – 14 November 1716) was a German polymath active as a mathematician, philosopher, scientist and diplomat. He is one of the most prominent figures in both the history of philosophy and the history of mathem ...
and Descartes discussed the infinite divisibility of extension. Actual divisibility may be limited due to unavailability of cutting instruments, but its possibility of breaking into smaller pieces is infinite.
Compenetration
''Compenetration'' refers to two or more extensions occupying the same space at the same time. This, according to scholastic philosophers, is impossible; according to this view, only spirits or spiritualized matter can occupy a place occupied already by an entity (matter or spirit)
Extended Mind Thesis
In more recent work, philosophers David Chalmers
David John Chalmers (; born 20 April 1966) is an Australian philosopher and cognitive scientist specializing in the areas of philosophy of mind and philosophy of language. He is a professor of philosophy and neural science at New York Universi ...
and Andy Clark in 1998 published "The Extended Mind
In philosophy of mind, the extended mind thesis (EMT) says that the mind does not exclusively reside in the brain or even the body, but extends into the physical world. The EMT proposes that some objects in the external environment can be part of ...
." This has opened a wide channel of new research at the nexus of epistemology, philosophy of mind, cognitive and neuro-science, dynamic systems thinking, science, technology & innovation studies.
See also
* Mass
Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different elementar ...
* Mass generation
In theoretical physics, a mass generation mechanism is a theory that describes the origin of mass from the most fundamental laws of physics. Physicists have proposed a number of models that advocate different views of the origin of mass. The probl ...
* Higgs mechanism
In the Standard Model of particle physics, the Higgs mechanism is essential to explain the generation mechanism of the property "mass" for gauge bosons. Without the Higgs mechanism, all bosons (one of the two classes of particles, the other bein ...
References
{{DEFAULTSORT:Extension (Metaphysics)
Metaphysics of science
Concepts in metaphysics