Session 7
Rationalism
Rationalism is not merely a view that says we use reason to test truth. Rationalism says that we can determine all truth by logic. It says that we can rationally prove the existence and nature of God. For a rationalist, no appeal to evidence can overturn a logical demonstration. That is why Spinoza, having proven to his own satisfaction that all reality was unified in absolute being, denied that anything in the world had existence distinct from God, or that there was any free will. That is why Leibniz maintained that this is the best of all possible worlds, no matter how bad things get. He was convinced by rationalism that only the greatest good can exist. All truth is logically necessary to a rationalist.
The big problem with rationalism is that it is a castle built in the air that has no link with reality. It assumes—but does not prove—that the rationally inescapable is the real. In fact, in all of its logical rationalizing, it never proves that anything real even exists. The only way that rationalism can overcome these weaknesses is to quit being rationalism and begin accepting some empirical evidence.
Also, my own existence is actually undeniable, but it is not logically necessary. There is nothing in my existence that even suggests that I, or anything else, must exist, yet rationalism says, again without solid proof, that this is logically necessary. Finally, when rationalism tries to prove its own principles to offer a justification for itself, it fails doubly. The attempt itself is futile because everyone from Aristotle to the present has agreed that first principles cannot be proven; they must be self-evidently true and in need of no further explanation.
Rationalism as a philosophy stresses reason as the means of determining truth. Mind is given authority over senses, the a priori over the a posteriori
Although Aristotle (384–322 B.C.) believed that knowledge began in the senses, his stress on reason and logic made him the father of Western rationalism. René Descartes 1596–1650), Benedict Spinoza (1632–1677), and Gottfried Leibniz (1646–1716) were the chief modern rationalists.
Most worldviews have at least one major rationalist proponent. Leibniz embraced theism. Spinoza held to pantheism. Ayn Rand (1905–1977) professed atheism. Most deists (see DEISM) held some form of rationalism. Even pantheism is represented by strong rationalistic proponents, such as Charles Hartshorne (b. 1897).
The reason that various worldviews all have forms of rationalism is that rationalism is an epistemology, whereas a worldview is an aspect of metaphysics. Rationalism is a means of discerning truth, and most worldviews have exponents who use it to determine and defend truth as they see it.
Foundationalism. Foundationalism believes that there are first principles of all knowledge, such as the principle of noncontradiction, the principle of identity, and the principle of the excluded middle (see LOGIC). Certain foundationalists believe there are other principles, either the principle of sufficient reason (see SUFFICIENT REASON, PRINCIPLE OF) or the principle of causality (see CAUSALITY, PRINCIPLE OF). All rationalists are foundationalists, and all foundationalists believe in some foundational principles.
Objectivism. Rationalists also believe that there is an objective reality and that it can be known by human reason. This distinguishes them from mysticism, existentialism, and other forms of subjectivism. For a rationalist, the real is rational, and reason is the means of determining what is real.
Exclusivism. Rationalists are also exclusivists. They believe that mutually exclusive opposites cannot both be true. According to the law of noncontradiction, if atheism is true, then all nonatheism is false. If Christianity is true, then all non-Christian systems are false.
A Priorism. All rationalists believe there is an a priori element to knowledge. Reason is in some sense independent of experience. Even rationalists who are also empiricists (for example, Thomas Aquinas, Aristotle, and Leibniz), believe that there is nothing in the mind that was not first in the senses except the mind itself. Without this a priori (independent of experience) dimension to knowledge, nothing could be known.