Empiricism v. rationalism
THE EMPIRICISTS: Empiricists share the view that there is no such thing as innate knowledge, and that instead knowledge is derived from experience (either sensed via the five senses or reasoned via the brain or mind). Locke, Berkeley, and Hume are empiricists (though they have very different views about metaphysics).
The rationalists: Rationalists share the view that there is innate knowledge; they differ in that they choose different objects of innate knowledge. Plato is a rationalist because he thinks that we have innate knowledge of the Forms [mathematical objects and concepts (triangles, equality, largeness), moral concepts (goodness, beauty, virtue, piety), and possibly color – he doesn’t ever explicitly state that there are Forms of colors]; Descartes thinks that the idea of God, or perfection and infinity, and knowledge of my own existence is innate; G.W. Leibniz thinks that logical principles are innate; and Noam Chomsky thinks that the ability to use language (e.g., language rules) is innate.
Empiricism (In favor of Empiricism, against Rationalism):
1. Empiricism is Simpler: Compared to Empiricism, Rationalism has one more entity that exists: Innate knowledge. According to the Empiricist, the innate knowledge is unobservable and inefficacious; that is, it does not do anything. The knowledge may sit there, never being used. Using Ockham’s Razor (= when deciding between competing theories that explain the same phenomena, the simpler theory is better),1 Empiricism is the better theory.
2. Colors: How would you know what the color blue looks like if you were born blind? The only way to come to have the idea of blue is to experience it with your senses. (This objection only works possibly against Plato; see the introduction above again to see why this objection would not faze Descartes, Leibniz, or Chomsky.)
3. Imagination and Experience: How can we get the idea of perfect triangularity? We can extrapolate from our experience with crooked, sensible triangles and use our imagination to straighten out what is crooked and see what perfect triangularity is.
4. Rationalists have been Wrong about Their “Innate Knowledge”: Some medieval rationalists claimed that the notion of a vacuum was rationally absurd and hence it was impossible for one to exist. However, we have shown that it is possible.2 Reason is not the only way to discover the truth about a matter.
5. The Advance of Science: Much of science is founded on empiricist principles, and would not have advanced without it. If we base our conclusions about the world on empiricism, we can change our theories and improve upon them and see our mistakes. A rationalist seems to have to say that we’ve discovered innate knowledge and then be embarrassed if he or she is ever wrong (see examples such as the vacuum, above).
6. All Rationalists do Not Agree about Innate Knowledge: Rationalists claim that there is innate knowledge that gives us fundamental truths about reality, but even among rationalists (e.g., Plato, who believes in reincarnation and Forms and Descartes, who does not believe in either but does believe in a soul), there is disagreement about the nature of reality, the self, etc. How can this be, if there is innate knowledge of these things?
Rationalism (In favor of Rationalism, against Empiricism):
1. Math and Logic are Innate: Doesn’t it seem that mathematical and logical truths are true not because of our five senses, but because of reason’s ability to connect ideas?
2. Morality is Innate: How do we get a sense of what right and wrong are with our five senses? Since we cannot experience things like justice, human rights, moral duties, moral good and evil with our five senses, what can the empiricist’s ethical theory like? Hume (an empiricist) says morality is based solely on emotions; Locke says experience can provide us with data to show what is morally right and wrong, but does it seem that way to you?
3. Verifying Empiricism: Locke (an empiricist) says that our experiences tell us about the nature of reality, but how can we ever check our experience with what reality really is, in order to know that? Rationalists do not think we can, so we have to rely on reason.
4. Poverty of Stimulus Problem: Three year olds use language in ways that they are not explicitly taught. For example, they form original sentences from words that they haven’t heard put together in precisely that way before. Also, they start to understand grammatical rules before they even know what a noun or a verb is. If we can only say what we’ve heard said by others, how can three year olds speak as well as they do? This is known as the poverty of stimulus problem. You may think that Rationalism is strange, but it does a better job of explaining this problem than Empiricism. One way of choosing which of two theories is better (in addition to or instead of Ockham’s Razor – see Empiricism point #1 above) is asking, “Which theory explains the phenomena better?”1
5. Empiricism Undermines Creativity? According to Empiricism, you can combine things, separate them, and nothing else. With Rationalism, we come to experience with ready-made tools for creativity. E.g., Plato would say that we’re in touch with abstract, immutable realities, which provide lots of material with which to create.
6. Controllable Humans? According to Empiricism, human beings can be controlled and manipulated exceptionally easily. If we are nothing other than what we experience, then we should be able to be made to do whatever we’re taught. Rationalism has it that there is an invariable core (call it “human nature”) that refuses to be manipulated, which is what makes us unique.
1 I hasten to add that Ockham's Razor is simply a rule of thumb, and that I would recommend that the reader track down an excellent paper by Elliot Sober, entitled, "Let's Razor Ockham's Razor," wherein he demonstrates that if one uses Ockham's razor in a certain case of evolutionary biology, one will choose the wrong theory to explain the phenomena, because the situation is more complex than it may seem. I am persuaded by this argument and think we should not use Ockham's razor; I have it here because people seem to like using it, but hopefully they will be persuaded by Dr. Sober's argument as I am.
2 I have recently seen an episode of "Through the Wormhole" with God, I mean, Morgan Freeman, and scientists have apparently discovered that, even in a vaccum, there are some sort of subatomic particles there, so there is no such thing as nothing, or that even nothing is something.
© 2013 by David J. Yount