The story so far
We have been looking at different aspects of our common experience as human beings that are hard, if not impossible, to explain if our universe is no more than physical.
- Most neuroscientists find it hard to see why our consciousness, our unique sense of ourselves, would evolve in a purely physical world.
- If we are no more than physical, it seems impossible we can have true freedom of choice, yet that is what we experience.
- Most people believe some things really are right and wrong, yet in a physical world there is no objective basis for morality but only whatever we choose, either personally or as a culture.
All of these features of human life seem to imply there is truly something beyond the physical, something mental, or spiritual, lending support to the conclusion that a God exists who created the human race with these characteristics.
In this post we examine one more ability of human beings that may be the strongest indicator of all that God created the universe with the human race in mind – our ability to think and reason. This is perhaps the most difficult, and yet the most important, of this series so far.
Our cognitive faculties
Human beings are able to think and reason in a manner that is apparently way beyond the ability of any animals. Our cognitive processes include perceiving things around us, knowing about ourselves by introspection, and using intuition and reasoning to form conclusions. We can form beliefs, store knowledge in memory and choose to take action based on what we know.
All of this goes on in our brains via physical processes, both electrical and chemical, which follow well understood laws of physics.
Are our physical brains are totally responsible for our thinking?
The view that the whole universe, including our brains, is only made from physical stuff, is called physicalism. (“Naturalism” or “materialism” are more or less the same view.) On this view there is no God and no soul.
So how does our thinking work if physicalism is true?
If the world is no more than the physical, then everything that happens must have physical causes. And this includes our brains. So our beliefs and the thinking processes all have physical causes, namely the electrochemical processes in our brains. These physical processes totally explain all our cognition.
Mental events, the content of what we think, are caused by these physical events. But if physicalism is true, mental events don’t actually initiate action or other mental events, only physical events can do that. Moreover, these physical events (electrical or chemical activity in our brains) cannot be true or false, they just exist. The thoughts that accompany those events can be true or false, but they cannot influence our actions or conclusions.
Physicalism and logic
We are familiar with physical causation. A physical event occurs and, according to the laws of physics, there is some outcome. Cause and effect.
But we understand reasoning differently. It doesn’t work by cause and effect, but by what can be described as ground and consequence. If certain things are true, we can know other things are true according to the laws of mathematics or logic. For example, if I have an orange and you give me another orange (ground), I now have two oranges (consequence). 1 + 1 = 2.
Or to choose a more complex matter, if we are deciding how to vote in an election, we consider policies, weigh up the options (ground) and make a choice that we think will lead to the best – or least bad! – outcome (consequence)
But if physicalism is true, it doesn’t actually happen like this! We think we are reasoning, but the causes of our final conclusions are physical processes that are only affected by other physical events.
But to be caused is not to be proved – wishful thinking and delusions are caused but they are not grounded in reality. Physical cause and effect cannot produce ground-consequence logic, for physical events cannot be true or false.
So if physicalism is true, our acts of reasoning are governed by the laws of physics, not the laws of logic.
So how can we reason reliably?
Natural selection and reasoning
As the human race evolved, natural selection favoured the behaviour and genes which most assisted survival and reproduction. So our cognitive faculties would have evolved in this way to become more and more helpful in survival and reproduction.
But in evolution, behaviour is adaptive whereas beliefs are not. Natural selection can favour beneficial behaviours, but cannot select for true insights and beliefs. In fact there is no need for any belief at all for behaviour to be adaptive.
So while the ability to draw a conclusion, such as hearing a sound and concluding that a predator may be nearby, will certainly be beneficial to survival, the response to run doesn’t arise via intuition (for beliefs cannot influence actions directly), but as a result of a physical sequence of events in the brain.
So the only way physicalism can explain our reasoning processes is that the physical processes in our brains have evolved to mimic reasoning. The ability to draw a correct inference is somehow wired into the cause-effect physics of our brains.
How much can this explain?
I think we can see how this might work in simple cases. Take the example of an animal hearing the sound of a possible predator. The individuals that drew the conclusion quickly that a predator might be nearby and fled would be more likely to survive and reproduce than those that didn’t draw this conclusion.
But it is important to note that the prey species survived not because it learned (via natural selection) to reason or arrive at a true belief, but because it learned to flee.
It is also notable that the belief that a predator is there need not be true at all. Why should the beliefs which accompany brain states be true just because the brain states are beneficial? The belief that a predator was lurking might be untrue 99 times out of 100, and still the learned behaviour to flee at any sound would be a beneficial adaptive response. So in many cases, the beneficial response could be accompanied by a false belief.
Beliefs can only be improved by natural selection if they can influence survival. But if physicalism is true, they can’t influence survival because they can’t affect physical processes, but are only the result of physical processes.
And even if natural selection can lead to correct beliefs in matters affecting survival, because beliefs are closely tied to survival behaviour, this doesn’t lead to the ability to do abstract reasoning which has no benefit to survival and reproduction.
So even simple responses like this don’t demonstrate the ability to reason, though they show how our brains have evolved to sometimes reach reasonable beliefs which may assist survival and reproduction.
But it becomes difficult to see physicalism and natural selection can explain our ability to do complex mathematics or logic or to develop and test complex scientific hypotheses, or to psychoanalyse complex behaviours. Such reasoning and the resultant beliefs can’t be refined by natural selection because they don’t cause behaviour (i.e. they are epiphenomena).
Alternate explanations
We might argue that the belief formed by the prey animal was not that a predator was present (a false belief in many cases) but that there is a risk that a predator is present. But it remains true that the response was caused by physical processes and actions, not the cognitive ability to do risk assessment.
It is also often argued that a computer uses only physical processes yet it can perform logic steps, so why shouldn’t the brain be similar? But (1) the computer doesn’t make inferences, it merely follows the way it is programmed, and (2) the computer program was designed, a conclusion that a non-theist is not willing to draw.
But could not natural selection produce apparent design in our brains just like in a computer? Well, only what aids survival and reproduction, which doesn’t include higher reasoning. A physicalist has to believe that reasoning and beliefs that accompany survival behaviour, and can easily be faulty, can somehow develop into reliable abstract reasoning and cognition that can outdo that designed into computer programs.
The impasse of physicalism
So physicalism cannot adequately explain what is an obvious human ability. It cannot explain the reasoning which we use to arrive at the view we call physicalism.
Physicalism undermines itself.
I have never seen this difficulty adequately explained. Defenders of physicalism usually argue that natural selection can explain how the beliefs we hold are correlated to the behaviours that determine those beliefs.
But as I believe I have shown, natural selection based on behaviour can produce beneficial behaviours, but these are not necessarily accompanied by true beliefs, and the beliefs that accompany beneficial behaviours are not based on reasoning. Our apparent ability to reason would be accidental and unreliable.
This becomes a compelling reason to reject physicalism. Our universe must contain more than the physical or we could not reason our way to true conclusions.
Beliefs must be able to influence brain states and action.
One step at a time: a giant leap for humankind
I conclude that the human ability to reason to correct conclusions is a deal-breaker. It is possible to believe that we don’t have free will and ethics are subjective (the topics I discussed in previous posts), though I think such conclusions are not logical.
But it isn’t consistent to hold a belief that implies that we cannot reason, because we would be using reason to support that belief.
The inability of physicalism, naturalism and materialism to explain our ability to reason to a correct conclusion cannot, in my view, be dismissed or got around. Something else must be true.
The most obvious alternative belief is that there is indeed a creator God who made us with mental and spiritual capabilities that go beyond what physicalism can explain.
Non-theist philosophers such as David Chalmers and Thomas Nagel have also come to the conclusion that physicalism cannot be true, but believe this doesn’t necessarily mean theism is true and therefore there is a God. But so far they seem unable to show how reason can be effective in a physical universe without God.
I believe this really is a strong reason to believe in God, especially when allied with the difficulties non-theism has in explaining consciousness, free will and ethics. The world we all experience looks much more like a world God created to be more than physical, than a totally physical world.
Beyond science?
This conclusion isn’t supported by scientific investigation, though neither is it refuted by science. Science is naturalistic, it studies the physical world. It is thus limited in what it can confirm or refute. To use science to argue for physicalism is like arguing there are no colour television programmes while only having a black and white set.
On this matter, we need to go beyond science (which treats everything as an object) to our common experience and logic (which we know as subjects).
After all, we only know scientific truths via our cognitive faculties. So science isn’t fundamental, our thinking is. And our thinking shows us that the world must be more than merely physical.
Conclusion
In this series so far, I have concluded that non-theist philosophies (naturalism, physicalism and materialism) struggle to explain our universe (its existence and its “fine-tuning”) and our common experience as human beings (consciousness, free will, objective ethics and now cognition and reason). Each one of these present a case for theism, albeit some are not strong cases. But cumulatively, I believe the case is very strong. And we have 6 more reasons to go!
Next post, we will begin to examine apparent human experiences of God.
Sources I found helpful in preparing this
- Where the conflict really lies. Alvin Plantinga
- CS Lewis vs the new atheists. Peter Williams
- The recalcitrant imago dei. JP Moreland
- CS Lewis’s dangerous idea. Victor Reppert
- Thomas Nagel reviews Alvin Plantinga’s book, Where the conflict really lies. The New York Review of Books.
- Alvin Plantinga reviews Thomas Nagel’s book Mind and Cosmos. The New Republic
- Malcolm Thorndike Nicholson reviews Thomas Nagel’s book Mind and Cosmos. Prospect
- Brian Leiter and Michael Weisberg critically review Thomas Nagel’s book Mind and Cosmos. The Nation
Next page
7. The evidence for miraculous healing
Photo: David McEachan on Stocksnap.
What would be the difference between a world where physicalism is true, and a world where physicalism is false?
As best I can tell, there would be no difference. To me “physicalism” seems poorly defined and perhaps meaningless.
For that matter, what would be the difference between a world where there is a god, and a world where there are no gods? Again, I am unable to see any difference, which is why I am agnostic.
Why? Couldn’t there things that happen which are uncaused?
Physicalists believe that mental events are actually physical. And therefore they qualify as being able to cause other mental events.
My reasoning works by cause and effect. My thinking causes my reasoning.
Logic and reasoning are different things.
That you now have two oranges is a matter of logic. That you know that you now have two oranges is a matter of reasoning.
According to physicalists, your reasoning is a physical process and the decisions that you make in that reasoning are physical events.
That does not actually follow.
Our physical computers do logic. They follow the laws of logic. And they do that by entirely physical means.
Physicalists would say that beliefs are physical and can affect actions.
You have failed to show that.
Hi Neil, thanks for your interest and comments. It is good to have these ideas tested out, but your answers are too brief to offer any reason for me to amend anything I have written. So if you’d like to continue the discussion, let’s just pick one matter at a time, shall we? I’d like to start with this:
Can you explain this a little more please? If a mental event is actually physical (which is one form of physicalism, generally called reductive materialism), then we can say that a physical event in our brains has certain properties, most of them physical but one of them the mental content. For example, one physical event may include the mental proposition “I believe climate change is occurring.” Can you explain how you think this mental content property causes a new mental event (say the belief that I should change my behaviour), except via the physical properties?
Many physicalists — perhaps most physicalists — are supervenience physicalists. They say that everything supervenes on the physical. Or, equivalently, the physical facts determine all of the facts. They do not claim that there is a reductive account of this supervenience.
I don’t know why you would ask that.
I am not a physicalist. I have never claimed to be a physicalist.
It should have been clear from my previous reply, that I consider physicalism a dubious idea. Likewise, I consider mentalism a dubious idea.
Hi Neil, I am aware of the difference between reductive materialism and nonreductive (or supervenience) materialism. I only mentioned it because you said “Physicalists believe that mental events are actually physical.” which is reductive. Nonreductive would be, as you say in this comment “everything supervenes on the physical”.
But either way, it doesn’t matter, because I was attempting to explain why I thought physicalism (and materialism and naturalism) are not true. You apparently agree with me. I would be interested to know what view you DO hold then.
So let’s now look at this comment, where I said: “So if physicalism is true, our acts of reasoning are governed by the laws of physics, not the laws of logic.”
Your comment was: “That does not actually follow. Our physical computers do logic. They follow the laws of logic. And they do that by entirely physical means.”
That is exactly my point. The processes by which computers perform logic are totally physical, in this case electrical processes in the hardware. But the software has been designed to follow the laws of logic, though it could equally have been designed to be random or do bad logic.
Similarly, a human has hardware (the electrochemical processes in our brains) which has been “designed” by natural selection to do the logic. So the argument is, how could the coding of our brains have evolved via natural selection to do abstract logic when natural selection works be reinforcing survival and reproductive behaviour? How do beliefs or reasoning, which supervene on the physical, or relate to the physical in some way which you haven’t described to me, impact on the physical processes? What do you think?
No, I don’t agree with that.
“Physicalism is true”.
“Physicalism is not true.”
I see both of those as silly. I cannot see any meaning to “physicalism is true”.
As I see it, physicalism is a stance that some people take. I see it as a stance, but not as a description.
I don’t really agree with that, either.
Looking at it from a phyicalist stance, our computers are electrical appliances that do circuit switching. They don’t actually do logic at all. We interpret them as doing logic. And, in fact, we designed them with that interpretation in mind. But, from the viewpoint of a physicalist stance, there is no such thing as logic.
Similarly, if I adopt a physicalist stance toward humans, then they are not doing logic. I need to adopt a different stance (maybe Dennett’s “Intentional Stance”) if I am to see people as doing logic.
So maybe we should just avoid mixing our stances.
Hi Neil, I think you are being too cryptic for me, and you didn’t answer my two questions. So I can’t really see anything in what you have said that requires me to change anything I have said so far. But thanks for your interest.
Your questions presuppose that I am a physicalist. They are asking for my opinion as a physicalist. But since I am not a physicalist, I am unable to give such an opinion.
But, okay, I can try to comment anyway.
As far as I can tell, our brains do not do abstract logic. We may do abstract logic, and use our brains while doing so. But the brains are not doing the logic.
Many people are quite poor at doing logic. They have to learn how to do it. If our brains evolved to do logic, you would expect that to come more easily to us.
I doubt that beliefs even exist.
Yes, we describe people as having beliefs. But it is a rather crude description. It fits very poorly.
The beliefs don’t cause the behavior. Rather, we invent presumed beliefs as a way of explaining the behavior that we observe.
Hi Neil,
Neil, I appreciate hearing what you think, but I am finding this one difficult. I wrote a post criticising physicalism, and offering theism as an alternative. Theism implies something like dualism, though I didn’t spell that out here.
You criticised my post but didn’t offer any alternative viewpoint, so I assumed you were defending physicalism. Now I find you are not. So we both believe physicalism is mistaken. Thus the only belief “on the table” at the moment is theism/dualism. So you have offered me no reason to disbelieve in theism/dualism and no alternative view, though I do agree with some of what else you are saying. It doesn’t really leave me with anything to respond to.
Those are surely mistaken, too.
The world (or reality) is an interesting place. No matter how we try to describe it, we will probably be mistaken. Our attempts to describe can only be approximations, as best I can tell.
Ideas such as physicalism or theism or dualism come from our imagination. But why should reality be limited to what we can imagine?
The problem with physicalism, is that we do not know the meaning of “physical”. We keep learning new things, and whenever we do, we change what we mean by physical. For that matter, what we mean by “theism” and by “dualism” also change over time and vary between people.
Hi Neil,
If it is true that “we’ll probably be mistaken”, then 3 conclusions seem reasonable:
1. You cannot say strongly that physicalism is wrong or that theism/dualism is wrong. Or anything else, including that we are probably mistaken about things.
2. My theism/dualism makes more sense than any other belief, so, probably mistaken or not, I might as well stick to it.
3. There’s really no point in discussing anything, or really in thinking or doing anything, because we will probably be mistaken.
Doesn’t sound like a very helpful position to hold, especially as it is probably mistaken.
I used “mistaken” rather than “wrong”. To use “wrong” would be to suggest that this has moral implications — and that would be wrong.
You asked for opinions — or, at least, that seemed to be the point of your post. So I gave my opinion.
I have said that I am not a physicalist, and I have attempted to explain why. But I do not criticize other people for being physicalists. That’s for them to choose.
You seem to want to make this an issue of ultimate truth. I sincerely doubt that there is any such thing as ultimate truth. So, at most, I see this as having to do with a person’s outlook toward life and toward the world. We don’t have to all have the same outlook.
I don’t have a problem with that. I don’t think I have every tried to persuade you to give up your theism. If it works for you, then go with it.
I completely disagree with that.
We are members of a community (an international community). It is part of being a community, that we attempt to discuss our disagreements. Most of our remaining disagreements are relatively unimportant and are concerned with questions that don’t have to be answered. And we got that way because we do discuss disagreements and we are able to adapt so as to minimize disagreement on more important issues.
Hi Neil,
OK, but (1) you have only told me what you DON’T think is true, not what you DO think is true, and (2) all that you say is qualified by you scepticism about knowing anything (“No matter how we try to describe it, we will probably be mistaken. Our attempts to describe can only be approximations, as best I can tell.”)
I do. This site is named “Is there a God?” so I’m trying to answer big questions. I personally don’t see much point in settling for less.
So why do you discuss such questions? And how can there be no ultimate truth – SOMETHING must be true, surely? Surely you are only sceptical about whether we can know that truth?
We live in a world where geocentrism was once said to be true. And it is now said to be false.
So I look around at how people use “true”. And it is undoubtedly quite useful. But it is applied well beyond where it is useful. So I have a more limited view of “true”.
Maybe this partly comes from my being a mathematician. And, as a mathematician, I see that 3+3=1 is true if I am using the axioms of mod 5 arithmetic, but false with more traditional arithmetic. What is true depends on the axioms that we are assuming. So I see geocentrism as something like a set of axioms. If we assume those axioms, then some statements can be seen as true relative to those axioms. If, instead, we switch to heliocentrism as our set of axioms, we get different truths.
In practice, we use both sets of axioms. If you ever get a speeding ticket, the traffic cop will use the geocentrist axioms in his citation (listing your speed). But astronomers prefer the heliocentric axiom set for their work. In ordinary life, which axiom system to use is often implicit in the context of the discussion.
On questions such as physicalism, I see that as talk about proposed axioms. And we should not take proposed axioms to be either true or false. There role is as a standard for claims made on the basis of those axioms.
To say there is no ultimate truth, is just to say that there are no ultimate axioms.
That’s not about “knowing anything”. I am not a skeptic about knowledge. But I am skeptical about overreaching truth claims.
I reject the popular view that equates knowledge with truth. I see that as a mistake. Knowledge is in our ability to cope with reality. And if changing our axiom systems helps us better cope with reality, that’s an increase in knowledge — even if the adopted axiom system is seen as neither true nor false.
Hi Neil, sorry to take so long to reply, but the last few days have been crazy busy.
I’m also sorry to say that I don’t see a lot of reality in what you are saying here, for several reasons:
1. Some of your examples don’t “work”. Of course people once believed in geocentrism and sometimes it is still central and natural to think that way, but that doesn’t mean there is no ultimate truth about how objects in the universe move. And of course we can use the idea of modulus to write equations that seem counter intuitive to someone not familiar with it, but it is all just mathematics, quite understandable, predictable and true. I don’t think those examples demonstrate anything that is relevant to the discussion we have been having.
2. The view you seem to be hinting at – “there is no ultimate truth” – is obviously self contradictory. One just has to ask “Is that true?” If it isn’t, why think it? If it is, then it isn’t.
3. If you wanted to be consistent (which it seems like you don’t), then your opening comment, instead of making a number of statements culminating in “You have failed to show that.”, should have simply said “I don’t think we can know very much, including all you have written here – and anything I say as well.”
4. In the end, we live our lives and make decisions, make comments, form views, etc. We probably never have total certainty but most of us we get on well enough (except when the dangerous few rich and powerful impose their will on the rest of us, to evil effect!). So I discuss these things within that context. I can’t help feeling that your comments in this discussion are more like a game than reality. I’m sorry to be so frank, but it is a conclusion I have come to before when discussing with you.
So I think if we are to have any further discussion, it should be on topics like “Can we know any truths?” and “Is there any point in having discussions?” Thanks.