Monday 15 April 2024

Models, Metaphysics and Reality: How Philosophy keeps science on track


By Rob Hamilton

Does God exist? What is consciousness? How can we know what is real?

Questions such as these have always perplexed humanity and despite the great advances made over recent centuries in understanding the behaviour of the world around us, we seem to be no closer to answering these core questions about the nature of existence.

In my new book Anything Goes – A Philosophical Approach to Answering the God Question, I argue that, paradoxically, answers to these questions can be obtained – but only once we recognise that no knowledge of the true structure of reality is possible. What do I mean by this? Well, essentially that claims about the structure of reality are models that describe the way our experience of how the world behaves. It is these models that then become our reality.

Put short, all the world is models

The popular notion of how science progresses is that we are steadily, if slowly, getting closer to the truth about the nature of the world around us. Indubitably, as time has gone on, scientific advances have been made and, yes, we have reached the stage where two great theories, Einstein’s General Relativity and the Standard Model of particle physics, provide us with a nearly complete description of the universe. We just need some clever physicists to iron out a few wrinkles like dark matter and dark energy in a Theory of Everything, and then we will have arrived at the Truth of how reality is structured.

The naivety of this belief is striking, a point highlighted by 20th century philosopher of science, Karl Popper, when he pointed out that scientific theories can never be proven to be true. Rather, they are working assumptions about the way the world is, that are supported by the evidence. Until they aren’t. 

Take Newton’s theory of gravity: this was thought to be true until anomalies like the precession of the perihelion of the planet Mercury were discovered. Nowadays, it is Einstein’s theory that provides the correct answer. But this raises the possibility that if we manage to come up with a Theory of Everything, who is to say that one day we will not conduct an experiment or make an observation that contradicts this theory too? For this reason, even if physicists were to discover the true structure of reality, they could never know it! 

“Okay”, some might say. “Although we can never know that we have reached the truth, at least we can say that our current theories are ‘more true’ than the previous ones”. This view is known as Convergent Realism and was powerfully critiqued in a 1981 paper by the philosopher Larry Laudan. 

At the everyday level, Einstein’s theory actually provides only very slightly different results to Newton’s, but the way it characterises the universe is completely different. Newton’s theory is set in the common-sense world of three-dimensional space plus a separate conception of time. Einstein’s is based on the notion of curved four-dimensional spacetime. Who can say what the universe will look like according to the next theory? As Schrödinger quipped, quantum mechanics tells us that cats can be alive and dead at the same time and that the building blocks of our universe can be both waves and particles. Weird, yes, but might it be that the true nature of the universe is just as weird and perhaps even beyond our ability to comprehend? 

Ultimately, scientific theories are models of the way the universe works. They allow us to understand the universe in terms of its behaviour, and we can use them to predict how the macroscopic objects of our experience, such as tables, stars and light bulbs behave. They do this by characterising the universe in a certain way that helps us get to grips with it. Because, as humans, we just do not have the tools to find out what the universe is ‘really like’.

The Map is the territory

Now comes the plot twist. The surprising but unavoidable consequence of this conceptual speed limit, is that the structure or make-up of this reality that we are modelling is irrelevant! It is only reality’s behaviour that matters. It is reality’s behaviour that we are modelling and a good model will predict its behaviour well. But if reality’s structure is unknowable and elusive, then it will forever remain a shadowy mysterious thing lying behind the veil. It is only the structure and objects of our models that can be known to us. These are the things that we live by and that give our lives meaning. And so these are the only objects that can be considered ‘real’ in any meaningful sense – if the objects of our models are not real, then nothing is real.

And so, what we have here, I would argue, is a case of The Emperor’s New Clothes. Many scientists and physicists are aware that all of our understanding is in terms of our models, but avoid engaging with the implications of this, because it is unnecessary for day to day work and raises difficult questions. They cling to the idea that there must be a ‘right answer’ out there, because if there isn’t, then well doesn’t everything fall apart? Where are the standards of correctness? What is to stop us from just claiming that whatever we like is true? In my book, I argue that these worries are unfounded. Although the structure of reality is unknowable, the good news is that it does behave in a certain way. And so not all models are created equal.

Anything Goes

I like to call this way of thinking the ‘Anything Goes’ method, because with no knowable reality to assess our models against, the only standard of correctness is a consideration of whether your model produces sensible results. And there is more to modelling reality than just the laws of physics. Even the idea that there is some kind of external reality, that is the source of our experiences, is part of this model that gives us an explanation for why our experiences behave in the way they do. Ultimately, each of us needs to find a way of making sense of our experiences in a way that works for us. In that sense, Anything Goes.

I think that this way of thinking is revolutionary! Once we recognise that it’s all a matter of perspective – that there are no disembodied facts about the universe in any useful sense, we can make progress in all sorts of areas that have previously proved intractable. Does God exist? It depends on your model. Is Schrödinger’s Cat alive or dead? Well, from whose perspective? Schrödinger’s or the cat’s? How would we tell if an Artificial Intelligence model attained consciousness? 

In my book, in order to find answers to questions like this last one, I ask what it means to say that an entity that only exists as part of your model of reality has a mind of its own as well as whether solipsism could be true, what it’s like to be a bat and whether you could be a brain in a vat!



All these questions and more are addressed in Anything Goes – A Philosophical Approach to Answering the God Question, due to be released on Amazon on 3 June 2024.

Visit http://www.anythinggoesmetaphysics.com/  to find out more as well as for details of how to get a free advance copy.

3 comments:

Anonymous said...

This is an interesting and provocative viewpoint, Rob.

I’ll say I have always subscribed to the idea there will never be a theory of everything. I doubt that humanity will ever declare it has arrived at such a eureka moment in its model-building and understanding of reality. The reason is that any supposed theory of everything -- at its core hubristic and self-exceptionalist -- will only ever serve as a placeholder until the next theory of everything and then the next and next .. . frankly ad infinitum. As such, I place any supposed theory of everything under the heady rubric of the unknowable.

Speaking of the unknowable, another idea that nicely fits there is whether a god does or does not exist. You say that “it is a short step to finally settling the question of whether or not God exists.” Maybe I misunderstand. Surely there never has been, nor will there ever be, confirmable proof of a god’s existence. All arguments have fallen on their face, and always will. Therefore, to my mind, theism and atheism are equally disqualified, as neither has any kind of basis; only agnosticism naturally emerges as the solely rational takeaway from god’s unknowability.

One corollary relates to your reference to Karl Popper, who, as you know, asserted that hypotheses meriting credibility must be falsifiable. As you point out, he focused on scientific hypotheses; however, reserving his falsifiability solely to science seems suspiciously arbitrary. Rather, I would contend that Popper’s core tenet – the essential nature of falsifiability -- proves equally inopportune when also applied to hypotheses (arguments) that assert a god’s existence. Think of the consequences of foundational religious tenets, including faith, put to the crucible of falsifiability. Not to mention the of Popper’s falsifiability to miracles and of life after death. Enter, again, from stage left the inconvenience of surefire unknowability. I’m not sure “anything goes,” as I believe there’s method to the madness of trying to understand reality along the lines demonstrated by Thomas Kuhn’s so-called paradigm shifts in science, where some shifts -- as well as incremental changes in our understanding, for that matter -- are better underpinned by evidence than are others.

Anyway, wishing you well, Rob, with your new book.

Keith Tidman

Martin Cohen said...

Thanks for the comment, Keith. I would add, on the 'falsifiability' angle, that there are surely lots of things that we can't prove/ falsify. For example, that there are ancient humans living on other planets in the Milky Way, having flown there in spaceships long before our era. Or any comment about the future: they are not falsifiable until after the time has passed.

Rob Hamilton said...

Hi Keith, many thanks for your thoughts on this. As far as whether God might exist in a realist sense, I go back to the point that if the 'true nature' of reality is unknowable (if it even exists!), then it is irrelevant. "How can it possibly be irrelevant whether God actually exists?" one might reasonably challenge. I argue in the book that there are significant problems with the way this question is positioned. It is essentially a 'Pascal's Wager' type concern - what if I live my life with a model that says God doesn't exist, but in the end, it turns out that he does?

Without going into the full arguments here, perhaps I can present a couple of pieces of food for thought. One - I could extend Pascal's Wager to Pascal's rock-and-a-hard-place, where the options are either a) God exists or b) a monster exists who only spares the atheists. In this set-up, if Pascal gets it wrong, he is in trouble either way. And two - it could be argued that on death, the problem of proof doesn't suddenly go away. If by some mysterious mechanism, you die and there is a continuing awareness with lights, voices and music etc, how can you know that this is God and not that there is something else going on?

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