One of Locke’s most significant contributions to the philosophical realm is his support for the concept of tabula rasa. This Latin phrase translates as “clean slate” in English. The term originally described a wax-covered tablet used for writing which was erased by heating and smoothing the wax after use. The tabula rasa theory suggests that the mind is a blank slate at birth; all knowledge comes through experience and sensory perception.

Locke rejected the concept of innate knowledge, first popularized by Greek philosophers during the fourth century. Aristotle, for example, suggested that even a blank tablet contains words and characters that have not yet been written. Innatism suggests that humans are born with certain knowledge. Locke challenges the belief that humans are born knowing certain innate principles, such as the law of identity. This principle suggests that all humans understand that things exist. Another idea considered innate is the existence of God. The foundation of the argument for innate knowledge is the concept of universal consent, the idea that all people in the world agree on these principles. Locke argues that universal consent does not exist. If any persisting theory is examined across the globe, there will always be examples of cultures and individuals who challenge it.