Any philosophy magnifying the role played by unaided reason, in the acquisition and justification of knowledge. The preference for reason over sense experience as a source of knowledge began with the Eleatics, and played a central role in Platonism . Its most significant modern development was in the 17th-century belief that the paradigm of knowledge was the non-sensory intellectual intuition that God would have into the workings of all things, and that human beings taste in their acquaintance with mathematics. The Continental rationalists, notably Descartes, Leibniz, and Spinoza, are frequently contrasted with the British empiricists ( Locke, Berkeley, and Hume ), but such oppositions usually oversimplify a more complex picture. For example, it is worth noticing the extent to which Descartes approves of empirical enquiry, and the extent to which Locke shares the rationalist vision of real knowledge as a kind of intellectual intuition. In spite of the authority of Kant, the subsequent history of philosophy has tended to minimize or even to deny the possibility of a priori knowledge, so rationalism depending on this category has also declined. However the idea that the mind comes with preformed categories that determine the structure of our language and ways of thought has survived in the work of linguists influenced by Chomsky . The term rationalism is also used more broadly for any anti-clerical, anti-authoritarian humanism, but it is unfortunate that it is empiricists such as Hume who are in this other sense rationalists.
Philosophy dictionary. Academic. 2011.