*Previous posts in this series
In the last part of this series of posts I looked at the mind as a non-physical object. If there is anything non-physical in the universe then a purely physicalist/materialistic explanation of reality is inadequate. I argued that the mind is the defeater for physicalism. This time around I want to dig deeper into that by looking at an argument made popular by C.S. Lewis. It’s commonly called the “argument from reason”. Victor Reppert has spent much of his career exploring this part of Lewis’s work so I will take a lot of info from his writings.
The basic argument from reason goes like this:
- No thought is valid if it can be fully explained as the result of irrational causes.
- If naturalism is true, then all thoughts can be explained as the result of irrational causes.
- Therefore, if naturalism is true, then no thought is valid.
- But, if that is so, then the thought “naturalism is true” is not valid.
- Therefore, naturalism cannot be both true and validly thought.
Number one depends on the belief that thoughts are rational events. So if they can be fully explained by irrational causes such as electrical impulses or chemical interactions then they are not valid thoughts. Remember Liebniz’s thinking machine? He said you can’t get rational events from a machine built from irrational components. That is the assumption underlying #1. I don’t see a way around this one since thinking that your thoughts are irrational is pretty self-defeating. You might disagree with Liebniz but at your own peril I think. That would require demonstrating a way to produce rational though from non-rational components. That’s going to be a tough one.
Number two just explains the naturalistic understanding of mental events. A naturalist or physicalist will say that mental events are just biological neural net type systems and are fully explainable by a study of the brains chemical interactions or electrical patterns. They will say that when we observe a set of electro-chemical events taking place in the brain, that we are actually seeing the “thought” occur in front of our eyes. This is very hard to swallow though. If that is the case, then thoughts in the human brain are just like logic events inside a computer system. But data in a computer event is meaningless to the computer itself. The data it acts upon “represents” information. It uses the data structurally, not rationally. That was covered last time though. Let’s move on.
Here is the first conclusion. Number 3 is the logical conclusion of #1 and #2. Let’s say it this way: “No thought is really a thought if it can be fully explained biochemically, but if naturalism is true, then all thoughts can be explained biochemically. Therefore, if naturalism is true, then there are no real thoughts.” And this is exactly what physicalists say. Take this quote from Daniel Dennett:
“The first stable conclusion I reached … was that the only thing brains could do was to approximate the responsivity to meanings that we presuppose in our everyday mentalistic discourse. When mechanical push comes to shove, a brain was always going to do what it was caused to do by current, local, mechanical circumstances, whatever it ought to do, whatever a God’s-eye view might reveal about the actual meaning of its current states. But over the long haul, brains could be designed — by evolutionary processes — to do the right thing (from the point of view of meaning) with high reliability. … [B]rains are syntactic engines that can mimic the competence of semantic engines. … The appreciation of meanings — their discrimination and delectation — is central to our vision of consciousness, but this conviction that I, on the inside, deal directly with meanings turns out to be something rather like a benign “user-illusion”.”
So basically, thoughts as traditionally defined do not exist. They are just illusions. What’s really going on are biochemical and electromechanical events in the brain that are responses to environmental inputs. We just see them as thoughts because they reside internally and are approximately semantic in nature. Maybe it’s just me, but I always question a philosophy that relies upon all of humanity being somehow delusional. It’s the same way with Frued and Bertrand Russell. I am skeptical of there theories that nobody understands what is really going on except them. The rest of us are just “wanting” so bad for something else to be true that we trick ourselves into believing it.
Number four turns the argument to address it’s self-refutation. This is the achilles heel of all non-rational explanations for rationality. You just can’t explain things that way without undermining your own argument. If there are no such things as real(a.k.a rational) thoughts then the the thought that “naturalism is true” is not rational. Pretty straight-forward.
The conclusion(#5) is obviously that naturalism can’t be both true in reality and valid in theory. A philosophy that is in that predicament is in trouble. Evidently Lewis modified this argument somewhat after his debate with Elizabeth Anscombe(a catholic philosopher). Reppert says that the argument was modified as such:
“Lewis’s revised argument begins much the same as the previous argument, distinguishes between connection via cause and effect and connection by ground and consequent. The key passage, to me, is on page 16 of my edition:
“But even if grounds do exist, what exactly have they got to do with the actual occurrence of the belief as a psychological event? If it is an event, it must be caused. It must in fact be simply one link in a causal chain which stretches back to the beginning and forward to the end of time. How could such a trifle as lack of logical grounds prevent the belief’s occurrence or how could the existence of grounds promote it?”
What Lewis claims is that if there are reasons to believe something, if naturalism is true, they would have to be irrelevant to the actual production of beliefs. No one could ever believe in naturalism because there are good arguments for naturalism.”
This is similar to what I explained in the description of #2 above. It’s more of a refinement than a change, and Anscombe later commended this change as a sign that Lewis was an honest philosopher and wanted to be sure he got things right. Next time I want to delve into Alvin Plantinga’s “evolutionary argument against naturalism”. It might be the most powerful argument against naturalism in the modern era.