Continued from my closing statement «
Steve has now posted his closing statement. As usual, I’m reproducing it here for ease of reference. This is the final part of our debate. My thanks to Steve for an interesting and thought-provoking exchange.
What I wanted to achieve in this debate was to explain how what we call reasoning in humans can arise without any involvement of God. When we observe a human taking in information, interpreting it, and responding, do we need to involve a deity? I have shown why we don’t with a clear explanation of how the interaction of neurons in the human brain can give rise to what we call “reasoning”.
What I had to achieve to win the debate was far, far simpler. All I had to show was that an alternative to the Christian God would have fitted my opponent’s arguments just as well, so showing that the Christian God was not necessary.
I’ll do that now: Suppose, hypothetically, I assume that my opponent was correct in every respect including the trinitarian nature of the deity. However, as he has provided no justification for which trinity is necessary, other than it be somehow supernatural and universal, I’ll go for the Wyrd Sisters, the Norns of Norse mythology: the Fates. I claim this is far more compatible with the reality we observe, as there is no theodicy required. The Fates can be nasty. There – debate over. Actually, it is far simpler than that. Non-theistic dualism is logically consistent. Therefore, by definition, God is not necessary for dualism (“necessary” means required in all logically possible worlds). I could have dismissed your entire argument and won the debate in two sentences. But, that would not have given me the chance to investigate the nature of reasoning in physical systems, which I believe has been a truly fascinating subject to explore.
During this debate, you have taken a predictable path and tried to escape from this conclusion by attempting to define reasoning so that it only fits your purpose.
You have tried to define reasoning as necessarily non-physical. However, you don’t get to a non-physical domain using ontological arguments. You have to show that this domain exists, and how it interacts with the physical world. We know that reasoning involves neural activity, so any supposed non-physical system has to interact causally with neurons in order to feed back the supposed results of this non-physical processing. This “interaction problem” is a major issue with any theory of dualism, and unless you can come up with a solution, it is major question-begging to involve a non-physical realm. That is going to be hard to do, because without spacetime, there can be no causation. It is nonsensical to talk of objects which aren’t embedded in spacetime interacting with anything, let alone objects that are so embedded.
You also have tried to shift the ground by introducing subjective experience. That just won’t do. I was asked to discuss human reasoning in general, not what it feels like to reason. However, it is worth pointing out that good progress in understanding the nature of experience is being made, as can been seen from Paul Churchland’s work on the nature of the experience of colour. There is a question to be asked about why it is like anything to have experiences, but that is not the question we are dealing with here.
Reasoning is something we observe in others. If we can arrive at an outline of a materialistic explanation of how the interactions with others that we label as reasoning can occur – and we clearly can, as can be seen in the work of Paul and Patricia Churchland and others – then that explanation has to suffice. It isn’t acceptable to then declare that this can’t be reasoning simply because we know how it can occur! It does not matter what is performing the processing that appears us to be reasoning. It may be a human brain, it may be Ned Block’s “Chinese Nation” – the substrate of the logical processing is of no consequence.
Then you move on to a discussion of logical laws. The question of how the mathematical and logical landscape that we explore arises is interesting, and I agree with you on the key point: it could not have looked different. Once we start off with the axioms of number theory, and if we use base 10, then the digits of Pi have to be what they are. However, as you agree that this landscape could not have looked different, then you remove any involvement of a deity. As the logical and mathematical landscape is immutable, there are no “dials” for a deity to have had to “set” to tune the landscape so that it was as we see it.
As for the logical principles we use for reasoning, they are selected from our experience of reality at human scales. If our experience was at a larger scale, where the ultimate signal transmission speed (that of light) is significant, then we would not comfortably discuss ideas of simultaneity, or events having a fixed sequence in time. If our experience was at a much smaller scale, quantum effects would mean we would have lack of confidence in the idea of entities having a definite position or momentum. In quantum mechanics, a bivalent logic (A logical system with the law: “P OR not-P, but not P AND not-P”) wouldn’t make sense. Different logical systems appear to be useful at different scales. As our experience is on a scale ranging from milimetres to miles, we find certain logical and ontological systems useful, and, indeed, we have evolved that way. I have previously covered in some detail how evolution leads to aspects of human reasoning.
My closing words will be to continue a theme from my last statement: that we need to be humble, and not assume reality is centred around us.
Theism and supernaturalism are not just of no help in understanding reality, they aren’t capable of providing such an understanding. For example, suggesting causation between our physical world and a timeless supernatural realm is nonsensical: without time, there can be no causation. The arbitrary nature of supernaturalism means that it is useless for any understanding of reality, indeed it is hard to see how supernaturalism could ever be demonstrated, let alone investigated. To invoke the supernatural to explain phenomena is a mistake of the same kind as “God of the gaps” arguments, and like them it should not even be theologically acceptable.
Theism and supernaturalism are not just meaningless in terms of understanding reality, they can hold back our investigation of it. An example has been shown in this debate, with claims that reasoning must be non-physical. In other words, our investigation of the physical world in this context is pointless. This is the kind of claim that can be encouraged by theism – both premature and lacking in humility. If we humans don’t yet fully understand how a physical mechanism works – if our feeling of incredulity that some aspect of reality and our experience of it can be purely naturalistic in origin, then that is an end to it – it must be supernatural. I wonder how far future generations will look back on current views that humanity as it is now can be the arbiter of what is and isn’t possible in the material world.
Rational investigation involve the use of Ockham’s Razor – do not multiply entities unnecessarily: always go for the simplest real explanation. This is a vital principle of rational investigation, as it is our barrier against arbitrariness, and allows ideas to evolve, based on the foundation of existing knowledge, yet at the same time always opening up the possibility that mistakes in long-established ideas can be revealed. This requires we understand simplicity. The Christian God – ominipresent, omnipotent and omniscient – is complex beyond anything we can imagine, indeed infinitely complex. This is a problem for any attempt to use God as a rational explanation for any phenomenon – just about any alternative to the Christian God is simpler, and we are forced to consider that alternative due to Ockham’s Razor.
And it is amazing what we find when we do consider alternatives. We abandon vitalism and creationism and we discover biochemistry and evolution. We abandon celestial spheres and we discover a universe of a hundred billion galaxies. We abandon the soul and we discover a brain with a million billion synapses, each capable of processing information.
The stifling effect of assuming from the start that we are special can be seen in the way that religious views have held back science in an area of particular interest to me – astronomy. We humans simply had to be at the centre of things, and the cosmos had to be about and for us. Only when we humbly stand back can we see things as they really are, and what we see is amazing. Holy books and theologists did not lead us to quasars, or neutron stars or the picture of our universe when it was less than half a million years old painted by the cosmic microwave background. As we look at the universe in ever more detail, it may turn out that we are special, and that there is no other technological intelligence. But, this will be a far more impressive specialness than that implied by religion.
If we want to expand our understanding of the human mind, we have to again be humble and realise that we aren’t experts about what goes on in our own heads. We are in no position to state what is true or not about what our brains can achieve simply based on conceivability, or a desire to involve deities. We know that neural networks can process information in a way that we recognise as logical. We know that evolution can lead to the recognition and communication of truths between minds. Our modeling of the minds of others combined with awareness allows us to know what it is like to recognise meaning. There is not only no deity needed, but reasoning can, it seems, all be explained by the processing of information by nerve cells. The debate is over, and the result is surely clear. There is no need to move beyond the physical to explain how humans sense and interpret information, process it logically, and draw conclusions. Indeed, the more we explore the physical world, the more astonishing that world appears, as science takes us beyond the limits of imagination.