The argument from reason is a name applied to an argument,
or a group of arguments, which attempt to make a case against a naturalistic
philosophy by pointing out that such a philosophy undercuts the claim to hold
rational beliefs. The argument is best-known in the writings of C. S. Lewis,
but is considerably older. Some have actually found this line of argumentation
as far back as Plato, and a version of it is found in Kant.
What these arguments invariably target are doctrines known
as naturalism, materialism, or physicalism. All of these concepts are
notoriously difficult to define. What seems to be common to all of them is the
idea that at the basis of reality are elements which are entirely non-mental in
nature. We can begin thinking about this by contrasting two different types of
explanation. One type of explanation is what might be provided by how we might
explain the movement of rocks down a mountain in an avalanche. If I am standing
down at the bottom of the mountain, we can expect the rocks to move where they
do without regard to whether my head is in their path or not. They will not
deliberately move to hit my head, neither will they move to avoid it. They will
do what the laws of physics require that they do, and if my head is in the
wrong place at the wrong time, it will be hit, and otherwise it will not be
hit. The process is an inherently blind one.
Consider, by contrast, how we might explain what happens
when I decide to vote for a certain candidate for President. I weigh the
options, and choose the candidate who is most likely to do what I want to see
done in the country for the next four years. The action of voting for Obama or
Romney is one filled with intention and purpose. I know what the choice is
about, I have a goal in mind when voting, and I perform the act of voting with
the intent to achieve a certain result.
If we look at the world from a naturalistic perspective, we
are always looking to find non-mental explanation even behind the mental
explanations that we offer. Take, for example, Einstein developing his theory
of relativity. If a naturalistic view of the world is correct, then we can, and
must explain the development of Einstein’s theory in mental terms, in terms of
certain mathematical relationships obtaining, and so forth. But, Einstein’s
brain is, according to the naturalist, entirely the result of a purely
non-intention process of random variation and natural selection. The appearance
of intention and design is explained by an underlying blind process that not
only produced Einstein’s brain, but also, the processes in his brain are the
result of particles in his brain operating as blindly as the rocks falling down
the avalanche and either hitting or not hitting my head at the bottom of the
mountain.
Contrast this with a theistic view. On such a view, there may be particles the
follow the laws of physics, but those laws are in place because they were built
into creation by God. Presumably, if God had wanted there to be other laws of
physics, he could have made a world with laws of physics very different than
the ones that we see. So, on the theistic view we see the opposite of
naturalism. Even what seems on one level to be completely explained in terms of
the non-mental has a mental explanation.
The argument from reason tries to show that if the world
were as the naturalist, or materialist, or physicalist, says that it is, then
no one can be rational in believing that it is so. Rational beliefs must,
according to the argument, must have rational causes, but naturalism holds
that, in the final analysis, all causes are non-rational causes. But if this is
so, then human beings really don’t reason, and if they don’t reason, they don’t
do science either. So, the very naturalistic world-view which is supposed to be
based on science, is actually the very view that render science impossible.
In the original 1947 edition of his book Miracles: A
Preliminary Study, Lewis presented a version of the argument from reason which
can be formalized as follows.
1)
If naturalism is true, then all thoughts
including the thought “naturalism is true,” can be fully explained as the
result of irrational causes.
2)
If all thoughts that are the result of
irrational causes, then all thoughts are invalid, and science is impossible.
3)
If all thoughts are invalid, and science is
impossible, then no one is justified in believing that naturalism is true.
4)
Therefore naturalism should be rejected.
In 1948, the Roman Catholic philosopher
Elizabeth Anscombe argued that against Lewis’s argument in a paper at the
Oxford Socratic Club. She argued, first that one has to distinguish between
irrational causes on the one hand, and non-rational causes on the other.
Irrational causes for a belief would be such things as wishful thinking or
mental illness, or unreasonable fears. Irrational causes always interfere with
the possibility of believing rationally.
Non-rational causes would by physical events which, while not rational, don’t
necessarily make rationality impossible. While naturalists hold that all
thoughts are the result of nonrational causes, they need not hold that they are
the result of irrational cases.
Second, she argued that when we say that
something or other makes a thought invalid, we are presuming a contrast between
valid and invalid thoughts. Hence, the very existence of the distinction
entails that some thoughts are valid and others are not, and so it cannot be
the conclusion of an argument that no thoughts are valid.
Third, she argued that there is an
ambiguity in the terms “why,” “because” and “explanation” conceal the
possibilities that a naturalistic explanation and a rational explanation might
not actually turn out to be compatible. Thus, when we are asking “why” in the
context of identifying a cause for a certain event, we are asking a radically
different question from when we are asking “why” when we are asking why someone
believes something. Thus, we could simultaneously give “because such and such
brain event caused it,” and “because there is good evidence to think it true”
as explanations without contradicting ourselves.
Now, in response to these arguments by
Anscombe, some responses can be made on Lewis’s behalf. First, with respect to
Anscombe’s first argument, Lewis had already drawn the distinction between
nonrational and irrational causes, when he distinguished between two types of
irrational causes. He wrote:
“Now
the emotion, thus considered by itself, cannot be in agreement or disagreement
with Reason. It is irrational not as a paralogism is irrational, but as a
physical event is irrational: it does not rise even to the dignity of error.”
With
both nonrational causes, in Anscombe’s sense, and irrational causes, reason is
absent from the causal process. Yet, in paradigmatic cases reasoning that a
naturalist cannot deny ever occur, such as the reasoning process that led
Darwin to explain the variation in beak sizes on the Galapagos islands in terms
of natural selection, reasoning is definitely present. Naturalistic thinkers
frequently insist that people require evidence for their beliefs as opposed to
believing on blind faith, but this implies that reasons can and do play a
critical role in the production of many beliefs. If this were not so, there
would be no science.
Second,
while it might be unsound to argue that
there no thoughts are valid, the conclusion of Lewis’s argument is the
conditional statement, “If naturalism is true, then no thoughts are valid.” So,
even though Anscombe’s paradigm case
argument might show that there must be a contrast between rational and
irrational thoughts, Lewis can affirm that there is indeed such a contrast, but
existence of such a contrast can exist only if naturalism is false.
Third,
although causal relationships are different from evidential relationships, when
we think about being persuaded to believe something, we are inclined to suppose
that somehow the fact that an evidential relationship obtains is causally
relevant to the actual occurrence of belief as a psychological event. Anscombe
actually says “It appears to me that if a man has reasons, and they are good
reasons, and they genuinely are his reasons, for thinking something, then his
thought is rational, whatever causal statements may be said about him.”
(Anscombe, 1981, p.299.) But it seems to me that part of what it is for
something to be someone’s reasons for believing something has to do with the
role those reasons play not only in producing, but also sustaining that belief.
If someone gives a reason for believing something, but it turns out that the
presence or absence of that reason would have absolutely nothing to do with
whether or not a person continued to believe what he does, then it is
questionable whether these reasons are operative at all.
If you
were to meet a person, call him Steve, who could argue with great cogency for
every position he held, you might be inclined to consider him a very rational
person. But if you were to discover that he rolled dice to fix permanently all
his beliefs, you might on that account be inclined to withdraw from him the
honorific title “rational.” We sometimes consider persons who continue to hold
the positions they hold regardless of the evidence against such positions
impervious to reason. But if naturalism true, it might be argued that everyone
is impervious to reason, because, in the final analysis, because the existence
of reasons is irrelevant to how beliefs are produced and sustained. In the last
analysis, all beliefs are caused, not by mental, but rather by physical, and therefore
nonmental causes.
