Alchemy
Empedocles, an older contemporary of Socrates, made a fundamental contribution to the formation of the alchemical theory of matter. This philosopher is said to have been the first to explain that the natural world was composed of four primordial elements: fire, earth, water, and air, associated respectively with the properties: hot, cold, moist, and dry.
Empedocles called these four elements the botanical term roots (he never used the term elements, which seems to have been first used by Plato), as a metaphorical root for his theory of matter that the basic material of nature originates from the four primordial elements.
Platonic Solids
It was Plato who proposed underlying structure to the elements, offering a mathematical model of their composition. According to the theory of the Platonic solids, the structures of the four elements must be geometric: polyhedra with well-defined shapes. Fire consists of tetrahedra, earth of hexahedra, water of icosahedra, and air of octahedra.
Plato was already considering what his student Aristotle ultimately proposed, that there was a fifth element: aether, the material from which the heavens were made (which medieval alchemists later reinterpreted as quintessence), the most refined and potent distillation of matter, a cosmic substance they believed could reveal the hidden architecture of the universe.
These Platonic solids offer a mathematical model for representing the building blocks of the cosmos. Euclid later made it possible to visually calculate and artistically represent the surfaces of the material world, hence the name of his best known work: Elements.
Aristotle’s Influence
But how did the elements themselves combine to form physical matter? The elements are composed of four primary physical contraries: hot, cold, moist, and dry. According to Aristotle, the first two are active causes, and the latter two are the underlying matter. For example: fire is hot and dry, earth is cold and dry, water is cold and moist, and air is hot and moist. The elements are these contraries in the sense that it’s precisely the physical contraries themselves that we perceive in earth or water.
Here lies the core of the alchemical theory of matter. Manipulating the compositions is the key to mastering a substance and its form, and thus the transmutation of matter. However, alchemists weren’t trying to violate nature, they believed they were assisting or accelerating natural processes. They were collaborating with nature inside their laboratories: speeding its workings up, slowing them down, or guiding them along a more perfect path.