Editing Jabir ibn Hayyan (section)

== Chemical philosophy ==

=== Elements and natures ===
According to [[Aristotelian physics]], each [[Classical element|element]] is composed of two qualities: [[fire (classical element)|fire]] is hot and dry, [[earth (classical element)|earth]] is cold and dry, [[water (classical element)|water]] is cold and moist, and [[air (classical element)|air]] is hot and moist. In the Jabirian corpus, these qualities came to be called "natures" (Arabic: ''ṭabāʾiʿ''), and elements are said to be composed of these 'natures', plus an underlying "substance" (''jawhar''). In metals two of these 'natures' were interior and two were exterior. For example, lead was predominantly cold and dry and gold was predominantly hot and moist. Thus, Jabir theorized, by rearranging the natures of one metal, a different metal would result. Like [[Zosimos of Panopolis|Zosimos]], Jabir believed this would require a catalyst, an ''al-iksir'', the elusive elixir that would make this transformation possible&nbsp;– which in European alchemy became known as the [[philosopher's stone]].<ref>{{harvnb|Nomanul Haq|1994}}.</ref>

=== The sulfur–mercury theory of metals<!-- [[Sulfur-mercury theory of metals]] redirects here; please edit the redirect (via 'what links here') when changing the name of the section heading --> ===

The sulfur–mercury theory of metals, though first attested in [[Pseudepigrapha|pseudo]]-[[Apollonius of Tyana]]'s ''The Secret of Creation'' ([[Sirr al-khaliqa|''Sirr al-khalīqa'']], late 8th or early 9th century, but largely based on older sources),<ref>{{harvnb|Kraus|1942–1943|loc=vol. II, p. 1, note 1}}; {{harvnb|Weisser|1980|p=199}}. On the dating and historical background of the ''Sirr al-khalīqa'', see {{harvnb|Kraus|1942–1943|loc=vol. II, pp. 270–303}}; {{harvnb|Weisser|1980|pp=39–72}}.</ref> was also adopted by the Jabirian authors. According to the Jabirian version of this theory, [[metal]]s form in the earth through the mixing of [[sulfur]] and [[Mercury (element)|mercury]]. Depending on the quality of the sulfur, different metals are formed, with [[gold]] being formed by the most subtle and well-balanced sulfur.<ref>{{harvnb|Kraus|1942–1943|loc=vol. II, p. 1}}.</ref> This theory, which is ultimately based on ancient [[History of meteorology|meteorological]] speculations such as those found in [[Aristotle]]'s [[Meteorology (Aristotle)|''Meteorology'']], formed the basis of all theories of metallic composition until the 18th century.<ref>{{harvnb|Norris|2006}}.</ref>