Short answer
Alchemy is a premodern practice and philosophy concerned with the transformation of matter, and in many traditions, of the person doing the work. It is best known for the aim of turning base metals such as lead into gold with the help of a substance called the philosopher’s stone. Alchemists also sought medicines and elixirs, and many wrote about spiritual purification using the same imagery.
The core ideas
A few assumptions underlie most alchemical thinking:
- Matter can change. Alchemists did not think metals were fixed. A common idea was that metals grow slowly in the earth toward perfection, with gold as the most perfect, and that the alchemist could speed this up.
- Everything shares a common basis. Many traditions held that all substances come from one underlying matter or from a few principles. In the West, the four elements (earth, water, air, fire) were widely used. Some Arabic and later European writers also described metals as combinations of sulphur and mercury. Paracelsus added salt as a third principle.
- Nature and the human are linked. The idea of correspondences, summed up in the saying “as above, so below,” meant that processes in the lab could mirror processes in the cosmos or the soul. See the Emerald Tablet.
The philosopher’s stone and the elixir
The philosopher’s stone was said to be a substance that could transmute metals. Many writers also described it as a medicine that could heal or prolong life, which links it to the elixir of life. No such substance was ever produced. Alchemical texts rarely give a clear recipe and often use coded language, so even scholars debate what particular passages meant.
Matter and spirit
Alchemical texts frequently describe the work in stages of dissolution, purification and recombination, sometimes marked by color changes: black, white and red. Many authors compare this to the purification of the soul. Others describe laboratory procedures with little spiritual comment. The history of these strands is covered in more detail in the alchemical tradition.
The symbolic language
Alchemists used a rich set of symbols: the sun and moon for gold and silver, a serpent eating its tail (the ouroboros) for cycles and unity, and the “chemical wedding” for union of opposites. Planets were linked to metals. These images were partly a code and partly a way of expressing the idea that opposites can be reconciled. Later Hermetic and Rosicrucian writers used them too.
Is alchemy science or spirituality?
The honest answer is both, depending on the author and period. Many alchemists did real experimental work, and some of their methods contributed to the later development of chemistry. They also held a worldview in which matter and spirit were connected. Modern attempts to read alchemy as only chemistry or only psychology each miss part of the picture. In the twentieth century Carl Jung read alchemy as a symbolic account of inner change, an approach which is influential but is not how most alchemists would have described their work.
Learn more
For the history from Alexandria to the Renaissance, go to the alchemical tradition. For the wider context of which alchemy forms a part, see Western esotericism.