Deism From Wikipedia, the free encyclopedia. Deism is a religious philosophy which holds that reason and observation of the natural world, without the need for organized religion, can determine that the universe is the product of an all-powerful creator. According to deists, the creator rarely, if ever, either intervenes in human affairs or suspends the natural laws of the universe. Deists typically reject supernatural events such as prophecy and miracles, tending instead to assert that a god (or "the Supreme Architect") does not alter the universe by intervening in it. This idea is also known as the clockwork universe theory, in which a god designs and builds the universe, but steps aside to let it run on its own. Two main forms of deism currently exist: classical deism and modern deism.