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).
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.
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.
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
Photo: David McEachan on Stocksnap.