This is a list of substances or materials generally considered discredited. A substance can be discredited in one of three ways: #It was widely believed to exist at one time but no longer is. Such substances are often part of an

obsolete scientific theory This list catalogs well-accepted theories in science and pre-scientific natural philosophy and natural history which have since been superseded by scientific theories. Many discarded explanations were once supported by a scientific consensus, b ...

. #It was once believed to have drastically different properties from those accepted now. It was widely claimed and believed to possess significant properties that are no longer attributed to it. #It is currently believed to exist as part of a theory that has not met the theoretical and experimental requirements of mainstream

science Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence for ...

. In particular, such a theory must be predictive.

Substances whose existence is discredited

Substances whose properties are discredited

This is not to be construed as implying that these items––are discredited. What is listed are fire, water, metal, etc. as universal principles or fundamentals. *

Classical element Classical elements typically refer to earth, water, air, fire, and (later) aether which were proposed to explain the nature and complexity of all matter in terms of simpler substances. Ancient cultures in Greece, Tibet, and India had simil ...

s and Chinese elements discredited by

atomic theory Atomic theory is the scientific theory that matter is composed of particles called atoms. Atomic theory traces its origins to an ancient philosophical tradition known as atomism. According to this idea, if one were to take a lump of matter a ...

and

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 ...

. **

Fire (classical element) Fire is one of the four classical elements along with earth, water and air in ancient Greek philosophy and science. Fire is considered to be both hot and dry and, according to Plato, is associated with the tetrahedron. Greek and Roman tradition F ...

Water (classical element) Water is one of the classical elements in ancient Greek philosophy along with air, earth and fire, in the Asian Indian system ''Panchamahabhuta'', and in the Chinese cosmological and physiological system ''Wu Xing''. In contemporary esoteric trad ...

Earth (classical element) Earth is one of the classical elements, in some systems being one of the four along with air, fire, and water. European tradition Earth is one of the four classical elements in ancient Greek philosophy and science. It was commonly associated wi ...

** Air (classical element) **

Wood (classical element) In Chinese philosophy, wood (), sometimes translated as Tree, is the growing of the matter, or the matter's growing stage. Wood is the first phase of Wu Xing. Wood is the lesser yang character of the Five elements, giving birth to Fire. It stands ...

Metal (classical element) In Chinese philosophy, metal or gold (), the fourth phase of Wu Xing, is the decline of the matter, or the matter's decline stage. In Traditional Chinese Medicine Metal is yin in character, its motion is inwards and its energy is contracting. It ...

Aether (classical element) According to ancient and medieval science, aether (, alternative spellings include ''æther'', ''aither'', and ''ether''), also known as the fifth element or quintessence, is the material that fills the region of the universe beyond the terrest ...

: Now known not to exist (see above) * The four bodily humours: Blood, Phlegm, Black Bile, and Yellow Bile. Fluids believed to determine health and character. Discredited by modern

biology Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary i ...

, including discovery of

hormones A hormone (from the Ancient Greek, Greek participle , "setting in motion") is a class of cell signaling, signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and beh ...

. * The ''

tria prima Paracelsus (; ; 1493 – 24 September 1541), born Theophrastus von Hohenheim (full name Philippus Aureolus Theophrastus Bombastus von Hohenheim), was a Swiss physician, alchemist, lay theologian, and philosopher of the German Renaissance. He w ...

'' of

Paracelsus Paracelsus (; ; 1493 – 24 September 1541), born Theophrastus von Hohenheim (full name Philippus Aureolus Theophrastus Bombastus von Hohenheim), was a Swiss physician, alchemist, lay theologian, and philosopher of the German Renaissance. He w ...

and later

alchemy Alchemy (from Arabic: ''al-kīmiyā''; from Ancient Greek: χυμεία, ''khumeía'') is an ancient branch of natural philosophy, a philosophical and protoscientific tradition that was historically practiced in China, India, the Muslim world, ...

: Salt, Mercury and Sulphur. Discredited by modern

chemistry Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions ...

(the

and modern understanding of elements and compounds).

References

{{DEFAULTSORT:Discredited substances Obsolete scientific theories Chemistry-related lists Pseudoscience

Substances whose existence is discredited

Substances whose properties are discredited

See also

References