What does descartes think about knowledge

His last major work, Les Passions de l'âme (1650), written at the request of Princess Elizabeth of Bohemia, explains the passions in accordance with his dualistic principles. The pineal gland in the brain is declared to be the place of interaction between body and mind. If the body affects the mind, the converse is also true; writing in Neostoical vein, and expressing values also embodied in the heroes of Pierre Corneille, Descartes exalts the free will of the ‘généreux’.

His ideas, powerful in their own right, are given added force by his rhetorical skill. His tone and style—even his choice between Latin and French—correspond to his projected readers, whose reactions are provoked, anticipated, and answered. The man is very present in the writing. At times he is disarmingly modest, at times fiercely ironic. His plain style is often lifted to a higher plane by the striding rhythm of his sentences and his striking images.

Descartes's philosophy, Cartesianism, exercised a great influence, even when when it was rejected. His cosmology, with its ‘horror of the vacuum’ and its planets whirled around in vortices (tourbillons) of ether, succumbed to Newtonian physics, though not before supplanting Aristotle in the colleges. His doctrine of ‘innate ideas’ was ousted, or at least modified, by Locke's sensationalism.

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innate ideas, in philosophy, concepts present in the mind at birth as opposed to concepts arrived at through experience. The theory has been advanced at various times in the history of philosophy to secure a basis for certainty when the validity or adequacy of the observed functioning of the mind was in question. Plato, for example, asserted the inadequacy of knowledge arrived at through sense experience; the world apparent to sense was only a temporal, changing approximation of an eternal, unchanging reality. The next important occurrence of a doctrine of innate ideas, not directly based on Plato, is in the work of René Descartes. Among the ideas Descartes took to be innate were the existence of the self: cogito ergo sum [I think, therefore I am], the existence of God, and some logical propositions like, from nothing comes nothing. John Locke, objecting that the doctrine encouraged dogmatism and laziness in thinking, advanced the classic attack on innate ideas. He argued that if certain ideas were innate they would be universally held and used, which is not the case. In contemporary discussion the question of innate resources of the mind has been the subject of dispute between behavioral psychologist B. F. Skinner and linguistic theorist Noam Chomsky. Chomsky has pointed out that the learning of a language and linguistic performance cannot be adequately explained by the empirical behaviorist model.

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The innate knowledge theory is based on the following four main assumptions:

1. Human beings are endowed with innate knowledge as part of their rational nature.

2. Innate concepts and ideas are not the result of experience

3. This innate knowledge is conceived of in a number of different ways, i.e. the soul’s recollection (Plato), innate ideas of God (Descartes), a sense of time, space, causality and comparison (Kant), innate grammar (Pinker and Chomsky) and innate moral grammar (Hauser)

4. The source of innate moral knowledge is believed to be selection pressure.

“The innate knowledge thesis contends that we have knowledge that is derived from our rational nature, but not from deduction or induction. Plato believed that reason is the heart of what it means to be human. In his view, human beings have knowledge through the “soul’s” recollection. The notion of innate knowledge suggests that we are certain of some things even when there is no way of explaining how we arrived at the idea. In addition to the notion that there is such a thing as innate knowledge, the innate concept thesis holds that we possess some concepts that do not depend on experience. They too are believed to be arrived at by virtue of the rational nature of humankind. Descartes, for example, recognised the existence of innate ideas, such as ideas about God.”