In the 1700's, epistemology (the branch of philosophy that studies the nature of knowledge, its presuppositions and foundations, and its extent and validity), rather than metaphysics, became important. Physics and Mechanics became models for knowledge. Philosophers adopted an empirical approach, and believed that experience and observation would give rise to fundamental ideas. All knowledge could then be built up from these ideas.
- John Locke 1632-1704, a English philosopher. In An Essay Concerning Human Understanding (1690) he set out the principles of empiricism, and his Two Treatises on Government (1690) influenced the Declaration of Independence. He rejected Descartes' philosophy of innate ideas or axioms. He declared that the mind is like a 'blank tablet' upon which experience writes.
- George Berkeley 1685-1753, was an Irish prelate and philosopher whose basic theory, directed against the materialism of Thomas Hobbes, is that to be is to perceive or to be perceived. His works include Treatise Concerning the Principles of Human Knowledge (1710).
- David Hume 1711-1776, a British philosopher and historian who argued that human knowledge arises only from sense experience. His works include A Treatise of Human Nature (1739-1740) and Political Discourses (1752).