I remember in my introduction to formal philosophy that there were 5 branches: ontology, epistemology, logic, aesthetics and ethics. Logic is arguably subsumed under mathematics, which has a connection with ontology and epistemology through physics, and ethics is part of all our lives, from politics to education to social and work-related relations to how one should individually live. Aesthetics is like an orphan in this company, yet art is imbued in all cultures in so many ways, it is unavoidable.
However, if you read about Western philosophy, the focus is often on epistemology and its close relation, if not utter dependence, on ontology. Why dependence? Because you can’t have knowledge of something without inferring its existence, even if the existence is purely abstract.
There are so many facets to this, that it’s difficult to know where to start, but I will start with Kant because he argued that we can never know ‘the-thing-in-itself’, only a perception of it, which, in a nutshell, is the difference between ontology and epistemology.
We need some definitions, and ontology is dictionary defined as the ‘nature of being’, while epistemology is ‘theory of knowledge’, and with these definitions, one can see straightaway the relationship, and Kant’s distillation of it.
Of course, one can also see how science becomes involved, because science, at its core, is an epistemological endeavour. In reading and researching this topic, I’ve come to the conclusion that, though science and philosophy have common origins in Western scholarship, going back to Plato, they’ve gone down different paths.
If one looks at the last century, which included the ‘golden age of physics’, in parallel with the dominant philosophical paradigm, heavily influenced, if not initiated, by Wittgenstein, we see that the difference can be definitively understood in terms of language. Wittgenstein effectively redefined epistemology as how we frame the world with language, while science, and physics in particular, frames the world in mathematics. I’ll return to this fundamental distinction later.
In my last post, I went to some lengths to argue that a fundamental assumption among scientists is that there is an ‘objective reality’. By this, I mean that they generally don’t believe in ‘idealism’ (like Donald Hoffman) which is the belief that objects don’t exist when you don’t perceive them (Hoffman describes it as the same experience as using virtual-reality goggles). As I’ve pointed out before, this is what we all experience when we dream, which I contend is different to the experience of our collective waking lives. It’s the word, ‘collective’, that is the key to understanding the difference – we share waking experiences in a way that is impossible to corroborate in a dream.
However, I’ve been reading a lot of posts on Quora by physicists, Viktor T Toth and Mark John Fernee (both of whom I’ve cited before and both of whom I have a lot of respect for). And they both point out that much of what we call reality is observer dependent, which makes me think of Kant.
Fernee, when discussing quantum mechanics (QM) keeps coming back to the ‘measurement problem’ and the role of the observer, and how it’s hard to avoid. He discusses the famous ‘Wigner’s friend’ thought experiment, which is an extension of the famous Schrodinger’s cat thought experiment, which infers you have the cat in 2 superpositional states: dead and alive. Eugne Wigner developed a thought experiment, whereby 2 experimenters could get contradictory results. Its relevance to this topic is that the ontology is completely dependent on the observer. My understanding of the scenario is that it subverts the distinction between QM and classical physics.
I’ve made the point before that a photon travelling across the Universe from some place and time closer to its beginning (like the CMBR) is always in the future of whatever it interacts with, like, for example, an ‘observer’ on Earth. The point I’d make is that billions of years of cosmological time have passed, so in another sense, the photon comes from the observer’s past, who became classical a long time ago. For the photon, time is always zero, but it links the past to the present across almost the entire lifetime of the observable universe.
Quantum mechanics, more than any other field, demonstrates the difference between ontology and epistemology, and this was discussed in another post by Fernee. Epistemologically, QM is described mathematically, and is so successful that we can ignore what it means ontologically. This has led to diverse interpretations from the multiple worlds interpretation (MWI) to so-called ‘hidden variables’ to the well known ‘Copenhagen interpretation’.
Fernee, in particular, discusses MWI, not that he’s an advocate, but because it represents an ontology that no one can actually observe. Both Toth and Fernee point out that the wave function, which arguably lies at the heart of QM is never observed and neither is its ‘decoherence’ (which is the measurement problem by another name), which leads many to contend that it’s a mathematical fiction. I argue that it exists in the future, and that only classical physics is actually observed. QM deals with probabilities, which is purely epistemological. After the ‘observation’, Schrodinger’s equation, which describes the wave function ceases to have any meaning. One is in the future and the observation becomes the past as soon as it happens.
I don’t know enough about it, but I think entanglement is the key to its ontology. Fernee points out in another post that entanglement is to do with conservation, whether it be the conservation of momentum or, more usually, the conservation of spin. It leads to what is called non-locality, according to Bell’s Theorem, which means it appears to break with relativistic physics. I say ‘appears’, because it’s well known that it can’t be used to send information faster than light; so, in reality, it doesn’t break relativity. Nevertheless, it led to Einstein’s famous quote about ‘spooky action at a distance’ (which is what non-locality means in layperson’s terms).
But entanglement is tied to the wave function decoherence, because that’s when it becomes manifest. It’s crucial to appreciate that entangled particles are described by the same wave function and that’s the inherent connection. It led Schrodinger to claim that entanglement is THE defining feature of QM; in effect, it’s what separates QM from classical physics.
I think QM is the best demonstration of Kant’s prescient claim that we can never know the-thing-in-itself, but only our perception of it. QM is a purely epistemological theory – the ontology it describes still eludes us.
But relativity theory also suggests that reality is observer dependent. Toth points out that even the number of particles that are detected in some scenarios are dependent on the frame of reference of the observer. This has led at least one physicist (on Quora) to argue that the word ‘particle’ should be banned from all physics text books – there are only fields. (Toth is an expert on QFT, quantum field theory, and argues that particles are a manifestation of QFT.) I won’t elaborate as I don’t really know enough, but what’s relevant to this topic is that time and space are observer dependent in relativity, or appear to be.
In a not-so-recent post, I described how different ‘observers’ could hypothetically ‘see’ the same event happening hundreds of years apart, just because they are walking across a street in opposite directions. I use quotation marks, because it’s all postulated mathematically, and, in fact, relativity theory prevents them from observing anything outside their past and future light cones. I actually discussed this with Fernee, and he pointed out that it’s to do with causality. Where there is no causal relation between events, we can’t determine an objective sequence let alone one relevant to a time frame independent of us (like a cosmic time frame). And this is where I personally have an issue, because, even though we can’t observe it or determine it, I argue that there is still an objective reality independently of us.
In relativity there is something called true time (τ) which is the time in the frame of reference of the observer. If spacetime is invariant, then it would logically follow that where you have true time you should have an analogous ‘true space’, yet I’ve never come across it. I also think there is a ‘true simultaneity’ but no one else does, so maybe I’m wrong.
There is, however, something called the Planck length, and someone asked Toth if this changed relativistically with the Lorenz transformation, like all other ‘rulers’ in relativity physics. He said that a version of relativity was formulated that made the Planck length invariant but it created problems and didn’t agree with experimental data. What I find interesting about this is that Planck’s constant, h, literally determines the size of atoms, and one doesn’t expect atoms to change size relativistically (but maybe they do). The point I’d make is that these changes are observer dependent, and I’d argue that there is a Planck length that is observer independent, which is the case when there is no observer.
This has become a longwinded way of explaining how 20th Century science has effectively taken this discussion away from philosophy, but it’s rarely acknowledged by philosophers, who take refuge in Wittgenstein’s conclusion that language effectively determines what we can understand of the world, because we think in a language and that limits what we can conceptualise. And he’s right, until we come up with new concepts requiring new language. Everything I’ve just discussed was completely unknown more than 120 years ago, for which we had no language, let alone concepts.
Some years ago, I reviewed a book by Don Cupitt titled, Above Us Only Sky, which was really about religion in a secular world. But, in it, Cupitt repeatedly argued that things only have meaning when they are ‘language-wrapped’ (his term) and I now realise that he was echoing Wittgenstein. However, there is a context in which language is magical, and that is when it creates a world inside your head, called a story.
I’ve been reading Bryan Magee’s The Great Philosophers, based on a series of podcasts with various academics in 1987, which started with Plato and ended with Wittgenstein. He discussed Plato with Myles Burnyeat, Professor of Ancient Philosophy at Oxford. Naturally, they discussed Socrates, the famous dialogues and the more famous Republic, but towards the end they turned to the Timaeus, which was a work on ‘mathematical science’, according to Burnyeat, that influenced Aristotle and Ptolemy.
It's worth quoting their last exchange verbatim:
Magee: For us in the twentieth century there is something peculiarly contemporary about the fact that, in the programme it puts forward for acquiring an understanding of the world, Plato’s philosophy gives a central role to mathematical physics.
Burnyeat: Yes. What Plato aspired to do, modern science has actually done. And so there is a sort of innate sympathy between the two which does not hold for Aristotle’s philosophy. (My emphasis)
Addendum: This is a very good exposition on the 'measurement problem' by Sabine Hossenfelder, which also provides a very good synopsis of the wave function (ψ), Schrodinger's equation and the Born rule.
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