Chapter 5 :Epistemology


There are several theories of how we come to know something.  These lectures will cover several of them.

 (NOTE:  You must read only those linked materials that are preceded by the capitalized word READ.)

Theories of Knowledge






Rationalism -in Epistemology

 Rationalism is a reliance on reason {Lat. ratio} as the only reliable source of human knowledge. In the most general application, rationalism offers a naturalistic alternative to appeals to religious accounts of human nature and conduct.

A psychological characterization of rationalism would describe it as an overly deductive way of thinking and to the molding of reality to fit one's theoretical understanding.

More specifically, rationalism is the epistemological theory that significant knowledge of the world can best be achieved by a priori means; it therefore stands in contrast to empiricism.

The first philosophers who are today referred to as having been rationalists include Descartes (1596-1650), Leibniz (1646-1716), and Spinoza (1632-1677). These thinkers thought they were defending a form of rational thought in the form of a science  against the older school of thought known as scholasticism.  The defense of science offered by Descartes included a form of dualism that carried over elements of tradition of the scholastics in a form of thinking that is  technical, deductive, and abstract. In Spinoza's Ethics the method is again deductive and modeled on the geometric system of Euclid's Elements. Rationalism is a method of thinking that is marked by being a deductive and abstract way of reasoning.

In ordinary usage rationalism is a basic sense of respect for reason or to refer to the idea that reason should play a large role in human life (in contrast, say, to mysticism). 

READ : on rationalism 

READ: rationalism  

So with RATIONALISM it is possible to have knowledge without having sensory experiences.  There is knowledge of logic and its laws or rules that are based upon reasoning and not sensory experience. There is a knowledge that is innate or born inside of us, that is to say that there are forms of knowledge that exists within our minds from the time we are born.

Links to Rationalism sites:  

Descartes’ Epistemology  READ:   the first five sections

Suggested Reading:  Descartes’ Meditations part I

For Descartes knowledge involves CERTAINTY and certainty exists in the form of clear and distinct ideas, which are ideas that are indubitable (not capable of being doubted).  These would be innate ideas that all rational beings are born with such as  knowledge of self, God, and the world.  But all knowledge is the result of acts of reasoning.

Links related to Descartes:

View: Dr. Richard Brown Descartes 1: The Method of Doubt   

Dr. Richard Brown Descartes 2:  A Priori Knowledge 


Distinguished the truths of reasoning which were necessary truths as in the rule of contradictions, and excluded middle (statements are either true or false) from the truths of fact which are not necessary but are contingent upon experience and sufficient reason needed to accept what the senses report.

Links to Leibniz sites:

Problems:   While the rationalist can explain knowledge of Mathematics and Logic , how are the rationalists to explain knowledge of the external world?

On Rationalism see also

Stanford Encyclopedia of Philosophy,

Internet Encyclopedia of Philosophy,

Encyclopedia Brittanica,

The Ism Book: a Field Guide to Philosophy

Proceed to the next section.

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Introduction to Philosophy by Philip A. Pecorino is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

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