Alchemy first appeared in Egypt's Ptolemaic kingdom during the Hellenistic period. During this time Greek culture was spreading, and influencing ideas and beliefs worldwide. Independent from Egypt and Europe, China began studying its own form of alchemy that shared many ideas and methods with its western counterpart but was much more spiritual and medicinal than physical.
Egyptians believed that their god Thoth was responsible for alchemy and worshiped him in their pursuit of knowledge. When Greek culture moved into Egypt, Thoth was replaced with Hermes who the Greek believed was one in the same.
Thoth was a major god depicted as a man with the head of an ibis or occasionally a baboon. He was the arbitration of godly disputes and was the god of:
Hermes was the messenger of the Greek gods and guided the dead to the underworld. He was known in Greek literature for his cunning and was the god of:
When Christians invaded Egypt in 48 BC, they burned down the library of Alexandria which was one of the largest and most significant in the world. Much knowledge was lost and it is assumed that alchemical knowledge went with it.
Hermes symbol the Caduceus (two snakes wrapped around a winged staff) became the symbol of alchemy and eventually, of medicine as it is today.
Both Thoth and Hermes become one in later Greek culture as the legendary figure Hermes Trismegistus. He is said to have been the founder of alchemy itself and to have written many texts including the Aesculapius, the Corpus Hermeticum and, most significant to alchemy, the fabled emerald tablets. People who believed in Hermes Trismegistus and his texts formed the religion Hermeticism which is what alchemy is based upon. Most alchemists where Hermetic.
After the assimilation of Egypt into Greece, alchemical ideas where taken up by some Greek philosophers and scientists whom made it there own. Aristotle was probably the biggest contributor as he laid the groundwork for alchemy in the centuries to come. He laid out that the four basic principles of creation were air, earth, water, and fire. He also stated that each of these elements had certain attributes that were a combination of dry, wet, hot, and cold. He also set up the idea for alchemy as he theorized that, through time, all things are growing to perfection. Alchemists from that time forward wanted to speed up this growth so that they could, eventually, turn impure matter like lead, into the purest substance, gold. Aristotle's work was later studied by European philosophers who started the alchemical movement.