rationalism

n. practice of accepting reason as the supreme authority in determining conduct or opinion; doctrine that the mind is the source of all knowledge (Philosophy)

In epistemology and in its broadest sense, rationalism is "any view appealing to reason as a source of knowledge or justification" (Lacey 286). In more technical terms it is a method or a theory "in which the criterion of truth is not sensory but intellectual and deductive" (Bourke 263). Different degrees of emphasis on this method or theory lead to a range of rationalist standpoints, from the moderate position "that reason has precedence over other ways of acquiring knowledge" to the radical position that reason is "the unique path to knowledge" (Audi 771).
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Noun
1. (philosophy) the doctrine that knowledge is acquired by reason without resort to experience
(hypernym) philosophical doctrine, philosophical theory
(classification) philosophy
2. the theological doctrine that human reason rather than divine revelation establishes religious truth
(hypernym) theological doctrine, religious doctrine
(hyponym) deism, free thought
3. the doctrine that reason is the right basis for regulating conduct
(synonym) freethinking
(hypernym) doctrine, philosophy, philosophical system, school of thought, ism

(n.)
The system that makes rational power the ultimate test of truth; -- opposed to sensualism, or sensationalism, and empiricism.
  

(n.)
The doctrine or system of those who deduce their religious opinions from reason or the understanding, as distinct from, or opposed to, revelation.
  

rationalism