The word alchemy is itself of Arabic origin, although its original significance is lost. Forms of alchemy have been practiced over many hundreds of years by the Greeks, Egyptians, Chinese, Indians, and Arabs, but in Europe it reached the peak of its popularity with a proliferation of new texts on the subject in the 16th and 17th centuries. It was practiced by figures as diverse as John Dee, Francis Bacon, Thomas Vaughan, Robert Boyle, and Isaac Newton. The popular image of alchemists was of secret brotherhoods and individual fraudsters (Ben Jonson's satirical play The Alchemist and Pieter Bruegel the Elder's drawing of the same name illustrate this), but it was not until the growth of modern science in the 18th century (to which alchemy had itself made no small contribution) that interest began to decline.
The Swiss psychoanalyst Carl Jung introduced a new approach to alchemy in the 20th century. He noted a close correspondence between the dreams and fantasies of his patients and the writings of alchemists, particularly in terms of recurrent symbols and images (such as sun and moon, king and queen, toad, dragon, eagle, and rose). He considered that alchemical literature could be explained in psychological terms, and he viewed the symbols as manifestations of a "collective unconscious." Although Jung's own life and work were profoundly influenced by his contact with alchemy, the impact on psychoanalytical theory has so far been limited.
Alchemy, sometimes known simply as "The Art," is an esoteric mixture of ancient wisdom and quasiscientific experimentation. Essentially it is about transformation, particularly the purification and perfection of base, unrefined materials. The transformation may be at a physical or spiritual level. At a physical level, it is usually expressed in terms of the attempt to transform base metals into gold, and it involves complex procedures in the laboratory. It may also be about transformation from sickness to health, or from old age to youth. At the spiritual level, the various alchemical processes in spiritual transformation may be symbolic of the attempt to perfect base human nature; the transformation and purification occur as a result of the spiritual experiences encountered on the journey through life.
Many key alchemical terms have meaning on the physical and spiritual levels simultaneously. For example, conjunction (sometimes called the alchemical marriage) refers in the laboratory to the fusing of mercury and sulphur, but at a spiritual level (especially in the writing of a Christian alchemist like Jakob Boehme) it refers to the soul's union with God; it is variously symbolized by the marriage of a king and queen, by sexual union, by astrological conjunction (e.g., of the sun and the moon) and by the figure of the hermaphrodite.
The goal of the "sacred philosophy" of the alchemists was to produce the Philosopher's Stone, which could then be used as the agent of all kinds of transformation, including turning base metals into gold, prolonging life, and curing the sick. The Stone could take a variety of forms, including powder or liquid, and was also known as the Elixir or Tincture. The alchemical process was thus to turn the prima materia ("ordinary matter"-although of course there was much debate about what was the best substance to start with) into the Philosopher's Stone by separating it into its components, purging its impurities, and reconstituting it in perfect proportion in its refined form. There was no precise formula for achieving this result. The alchemist had to create a model of the universe (or of human consciousness) within a sealed, preferably egg-shaped, glass vessel or flask. Through a complicated succession of gradual heating and distillation, the transformation of the prima materia could take place. The transformation required the "death" of the body or original substance, the ascension of the "soul," the reuniting of the two in a new way and the fixing of the volatile elements thus generated.
The sequence of 12 stages of the laboratory process are described by the 15th-century English alchemist, Canon George Ripley, as calcination, solution, separation, conjunction, putrefaction, congelation, cibation, sublimation, fermentation, exaltation, multiplication, and finally projection (i.e., the use of the Stone for transformation). The whole operation is described in the symbolic language of birth, marriage, death, resurrection, battles, dragons, birds, and celestial bodies. In a spiritual sense, the prima materia on which the alchemist works is himself, and (at least from a Christian perspective) Christ is the perfect Philosopher's Stone. When the alchemist seeks to free the soul (mercury) and spirit (sulphur) from the body (salt) and to reunite them in a purified form, he is seeking to purge himself of the impurity of sin, so that he can be made again in Christ's image. The alchemical process thus helps an understanding of God's will and purpose in creation. Many 17th-century Christian writers and poets use images drawn from alchemy to convey deep spiritual truths. George Herbert, for example, in his poem "The Elixir," claims to have found in the principle of doing every action as if for God "the famous stone that turneth all to gold."