Since human beings seek to control nature and since these supernatural forces are thought to govern the course of natural events, the control of these forces gives humans control over nature. The practice of magic is held to depend on the proper use of both the ritual and the spell. The practice of magic, in seeking its desired end, also frequently combines within its scope elements of religion and science. In the art of alchemy the process of transmuting a base metal into gold would require precise weights and volumes of acids, bases, and catalysts as well as the reciting of holy passages and prayers. Anthropologists often distinguish between two forms of magic, the sympathetic and the contiguous.
Sympathetic magic works on the principle that like produces like.
The Ojibwa of North America makes a wooden image of his enemy and then sticks pins into it. Since the doll represents the enemy, harm done to the doll will harm the enemy. Contiguous magic operates on the belief that things that have been in contact will continue to act on each other after the physical contact has ceased. The aborigines of Australia believe that they can lame a man by placing sharp pieces of quartz, glass, bone, or charcoal in his footprints. Not all magic is performed in order to harm or destroy, and for this reason a distinction is made between black magic and white magic.