Rationalism vs. Empiricism: Foundations of Knowledge

Understanding Empiricism

Empiricism is the philosophical theory according to which the origin and limits of knowledge are sensory experience. The best-known empiricists include Thomas Hobbes, John Locke, David Hume, and George Berkeley.

Understanding Rationalism

Conversely, Rationalism is the philosophical doctrine that recognizes no source of knowledge other than reason, thus rejecting revelation, faith, and the senses. In the history of philosophy, rationalism has a more limited meaning, beginning in the 17th century with the figure of the mathematician René Descartes.

Key Differences Between Empiricism and Rationalism

It is interesting to compare Empiricism and Rationalism through their core tenets:

1. Source of Knowledge

   For Empiricism, the source of knowledge is experience, while for Rationalism, it is reason. According to rationalism, knowledge progresses from innate ideas, which are necessary and a priori. For example, in Descartes, God is an innate idea that serves as a criterion of evidence and the foundation of all knowledge. For empiricism, the mind is like a 'tabula rasa' (clean slate), and therefore, any idea found within it comes from experience. Empiricism, therefore, performs a systematic critique of metaphysics.

2. Limits of Human Knowledge

   For Empiricism, human knowledge has limits, being restricted by sensory experience, while Rationalism holds absolute confidence in the powers of reason to know everything.

3. Approach to Science

   Rationalism sought a method to unify knowledge and took as a model for modern science only its mathematical aspect. Empiricism, inspired by Newtonian physics, adopted a more critical approach and emphasized the other aspect: the importance of experience.

4. The Problem of the External World

   Empiricists and Rationalists both agree that what the mind directly knows are ideas (not things), and thinking is reduced to linking ideas together. For this reason, empiricists attach great importance to the analysis of the psychological mechanisms that explain the association of ideas and the subject's isolation from reality. This focus on phenomena leads to the classic question of the existence of the external world. Descartes had to resort to God as a guarantee of the external world's existence. Locke considered it absurd to prove certain things, assuming that our ideas of sensation, at least those related to primary qualities, are an exact copy of the real world. Hume understood that the only guarantee of the external world is habit or custom, which produce in us the consistency and coherence of our perceptions, and their survival value.