Empiricism and rationalism dominated George Berkeley’s era. Empiricists emphasized the importance of experience, especially that gained through the senses, in the process of acquiring knowledge. From these direct observations, the human mind uses inductive reasoning to make larger generalizations and, thus, arrives at a more detailed knowledge of things.

By contrast, rationalists argued that the human mind can grasp truth through reasoning alone, without the mediation of the senses. Some rationalist thinkers believed that human beings possessed innate ideas or were born naturally knowing certain things. Empiricists, on the other hand, argued that the mind was a tabula rasa, or blank slate, and needed to be filled with sense experience to begin the process of knowledge. It has been argued that empiricism served as the foundation for the scientific method or studying the physical world through direct observation and experiment.

Empiricism became especially associated with British thinkers beginning in the late 17th century, while rationalist thought developed in France among philosophers such as René Descartes (1596-1650) and Nicolas Malebranche (1638-1715). The major British empiricist of Berkeley’s era was John Locke (1632-1704). In the Treatise, Berkeley quotes several passages from Locke (without attribution), including from the 1690 Essay Concerning Human Understanding, in which Locke describes the mind as a blank slate, which life fills with experience.