William of Ockham was a 14th-century English philosopher and theologian, best known for his principle of parsimony, often referred to as Ockham's Razor. This principle suggests that the simplest explanation, requiring the fewest assumptions, is usually the best one. Ockham's ideas significantly influenced the development of modern philosophy and science. He was a member of the Franciscan order and engaged in debates about the nature of universals, which are concepts that can apply to multiple instances. Ockham's work laid the groundwork for later thinkers, including Rene Descartes and David Hume, shaping the course of Western thought.