rationalism

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Reliance on reason as the best guide for belief and action.
• noun Philosophy The theory that the exercise of reason, rather than experience, authority, or spiritual revelation, provides the primary basis for knowledge.

from The Century Dictionary.

• noun In general, adherence to the supremacy of reason in matters of belief or conduct, in contradistinction to the submission of reason to authority; thinking for one's self.
• noun In theology:
• noun In general, the subjection of religious doctrine and Scriptural interpretation to the test of human reason or understanding; the rejection of dogmatic authority as against reason or conscience; rational latitude of religious thought or belief.
• noun More specifically, as used with reference to the modern sehool or party of rationalists, that system of doctrine which, in its extreme form, denies the existence of any authoritative and supernatural revelation, and maintains that the human reason is of itself, and unaided by special divine inspiration, adequate to ascertain all attainable religious truth.
• noun In metaphysics, the doctrine of a priori cognitions; the doctrine that knowledge is not all produced by the action of outward things upon the senses, but partly arises from the natural adaptation of the mind to think things that are true.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Theol.) The doctrine or system of those who deduce their religious opinions from reason or the understanding, as distinct from, or opposed to, revelation.
• noun (Philos.) The system that makes rational power the ultimate test of truth; -- opposed to sensualism, or sensationalism, and empiricism.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun philosophy The theory that the basis of knowledge is reason, rather than experience or divine revelation.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun (philosophy) the doctrine that knowledge is acquired by reason without resort to experience
• noun the doctrine that reason is the right basis for regulating conduct
• noun the theological doctrine that human reason rather than divine revelation establishes religious truth