Deism is a theological theory concerning the relationship between a creator and the natural world. Deistic viewpoints emerged during the scientific revolution of 17th-century Europe and came to exert a powerful influence during the 18th-century Enlightenment. Deism stood between the narrow dogmatism of the period and skepticism. Though deists rejected atheism, they often were called "atheists" by more traditional theists. There were a number of different forms in the 17th and 18th centuries. In England, deists included a range of people from anti-Christian to non-Christian theists.
For deists, human beings can know God only via reason and the observation of nature, but not by revelation or by supernatural manifestations (such as miracles) – phenomena which deists regard with caution if not skepticism. Deism is related to naturalism because it credits the formation of life and the universe to a higher power, using only natural processes. Deism may also include a spiritual element, involving experiences of God and nature.
The words deism and theism both derive from words for "god": the former from Latin deus, the latter from Greek theós (θεός).
Prior to the 17th Century the terms ["deism" and "deist"] were used interchangeably with the terms "theism" and "theist", respectively. ... Theologians and philosophers of the 17th Century began to give a different signification to the words... Both [theists and deists] asserted belief in one supreme God, the Creator... . But the theist taught that God remained actively interested in and operative in the world which he had made, whereas the Deist maintained that God endowed the world at creation with self-sustaining and self-acting powers and then surrendered it wholly to the operation of these powers acting as second causes.
Perhaps the first recorded use of the term deist (French: déiste) occurs in Pierre Viret's Instruction Chrétienne en la doctrine de la foi et de l'Évangile (Christian teaching on the doctrine of faith and the Gospel, 1564), reprinted in Bayle's Dictionnaire (1697) entry Viret. Viret, a Calvinist, flagged the term as a neologism (un mot tout nouveau),
and regarded deism as a new form of Italian heresy.
Viret wrote that a group of people believed in "some sort of God" like the Jews and Turks but regarded the doctrine of the evangelists and the apostles as a mere myth. According to him Deists wrongly misinterpreted the liberty given to them during the reform period.
In England, the term deist first appeared in Robert Burton's The Anatomy of Melancholy (1621).
Lord Herbert of Cherbury (1583–1648) is considered the "father of English deism", and his book De Veritate (1624) the first major statement of deism. Deism flourished in England between 1690 and 1740, at which time Matthew Tindal's Christianity as Old as the Creation (1730), also called "The Deist's Bible," gained much attention. Later deism spread to France (notably through the work of Voltaire), to Germany, and to North America.