Humean, All Too Humean

I intended this post to be a bit of reflection on agent causation and free will, but I was led in a more fundamental direction after concluding with Timothy o’Connor that an account of agent causation really depends on the impossibility of a Humean account of causation. This is a rather simple thesis that can be summed up as follows: agent causation (AC) takes as fundamental that causes really do necessitate their effects – let’s call this Real Causality (RC). Humean-ism (H) fundamentally denies that causes necessitate their effects. Therefore, the first step towards an account and defense of agent causation ought to begin with a look at the metaphysics of causation – more specifically, why we shouldn’t take H to be the case.

Tim Maudlin in his excellent volume ‘The Metaphysics Within Physics’ maps out H by way of two doctrines derived from a reading of David Lewis:

‘Doctrine 1 (Separability): The complete physical state of the world is determined by (supervenes on) the intrinsic physical state of each spacetime point (or each pointlike object) and the spatio-temporal relations between those points.’

‘Doctrine 2 (Physical Statism): All facts about the world, including modal and nomological facts, are determined by its physical state alone.’ (p. 51)

Maudlin then takes these ideas to task, drawing arguments against Doctrine 1 from quantum physics. Classical physics was indeed separable – the physical state of the universe is, more or less, determined by spatio-temporal relations, dispositions and properties in space and time. Maudlin spends a fair amount of time doing some pretty fancy math and comes to the conclusion that given quantum theory as a part of a true description of the world (which is a separate but related contention – Maudlin isn’t trying for an instrumentalist or consciousness-based interpretation of quantum theory here), separability cannot be sustained. He arrives here by an exposition of particle systems, spin states and entagled states, which is rather technical.

Doctrine 2 Maudlin takes to be indefensible as well, and I’ll quote him at length here:

‘It matters not whether one starts with Newton, who, in the Principia, simply announces his three laws of motion after giving the definitions of various terms, or whether one turns directly to any contemporary textbook on quantum theory, which will treat, e.g., the Schrodinger equation as a fundamental dynamical principle. Physicists seek laws, announce laws, and use laws, but they do not even attempt to analyze them in terms of the total physical state of the universe or anything else…Unlike reductive analyses of possibility, causality, and chance, reductive analyses of laws are not endorsed by scientific practice.

Indeed, scientific practice seems to preclude such an analysis. As we have seen, physical possibility is easily understood in terms of models of the laws of physics. Let us suppose (and how can one deny it) that every model of a set of laws is a possible way for a world governed by those laws to be. Then we can ask: can two different sets of laws have models with the same physical state? Indeed they can. Minkowski space-time, the space time of Special Relativity, is a model of the field equations of General Relativity (in particular, it is a vacuum solution). So an empty Minkowski space-time is one way the world could be if it is governed by the laws of General Relativity. But is Minkowski space-time a model only of the General Relativity laws? Of course not! One could, for example, postulate that Special Relativity is the complete and accurate account of space-time structure, and produce another theory of gravitation, which would still have the vacuum Minkowski space-time as a model. So under the assumption that no possible world can be governed both by the laws of General Relativity and by a rival theory of gravity, the total physical state of the world cannot always determine the laws. The only way out is either to assert that empty Minkowski space-time must be governed by both sets of laws, since it is a model of both, or (a more likely move) that it can be governed by neither set of laws, since neither is the simplest account of space-time structure adequate to the model (the simplest account is just Special Relativity). But how can one maintain that the General Relativistic laws cannot obtain in a world that is a model of the laws, and hence allowed by them? The necessity of distinguishing the physical possibilities (i.e. the ways the world could be given that a set of laws obtains in the world) from the models of the laws signals a momentous shift from philosophical analyses that follow scientific practice to analyses that dictate it.’ (p. 67-68)

There is no shortage of less physics-based reasons to not be a Humean, however. One might point out that Hume’s conclusions have force only if his empiricism is accepted, and there are many good reasons why that shouldn’t be accepted – modern philosophy is, in fact, partly composed of such rejections (Reid, Sellars, and the rejection of the positivists make up part of this history. The positivists, who claimed that non-analytic statements or statements that go beyond empirical justification are meaningless, are left in a position which doesn’t exactly aid one in the search for the laws of nature. Nor are things such as quarks and their flavors logical constructions out of sense-data). This isn’t to say that a wholesale rejection of Hume is called for – his observation that causation is not empirical is absolutely correct, though not his further conclusion that it doesn’t exist at all, since causation is very real though metaphysical category. But if the foundation for Humean-ism, which is a strict empiricism, isn’t sound, then we have far less reason to accept Humean-ism.

Given this all-too-cursory look at why we might not want to be Humean, what exactly follows? Concerning agent causation, we are left with a good bit of space with which to work, now that the shackles of Humean causation have been loosed – we are free to develop an account of agency and freedom in which agents are real causes of events.

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Stanley Jaki on Einstein’s Failure

‘The year of that Slovay Congress, was, it is well to recall, the year in which Heisenberg gave his derivation of the principle of indeterminacy concerning measurements in physics. One can therefore in a sense understand Einstein’s tactics in taking on the Copenhagen interpretation at its nerve center, which consisted in the insistence that measurements were inconceivable without someone doing them. Thus it would be argued that the act of measurement, which in one way or another implied pointer readings and therefore a reliance on light quanta, deprived the measurement of absolute precision. Such insistence when elevated into a first principle became equivalent to withdrawing into a citadel. Once confined to measurements within that citadel, one could declare that physical theory was limited to the measurable and therefore had no need of hidden variables. Withdrawal into that citadel also meant the the viewing of anything outside it as unreal. It was such a citadel that Einstein wanted to conquer from within, by trying to devise a thought experiment in which absolute precision was in principle possible. He was bound to fail for the very reason that no measurement is possible without observation. But it did not follow from this that knowledge of reality was equivalent to measuring it with absolute precision. Philosophically the citadel in question did not represent the full range of man’s knowing reality, and it certainly did not represent the full range of modern physics. Einstein’s own theory of relativity was a case in point, and all members of the Copenhagen school could have been forced to admit that it was a telling case.’ (Stanley Jaki, ‘The Road of Science and the Ways to God’, p. 209)

Physics, Metaphysics, Physics

I’ll be the first to say that a lot of physics and a lot of metaphysics goes right over my head. Whoosh. Modern analytic philosophy, which is what most folks mean when they say metaphysics, is about as comprehensible to me as advanced mathematics (I’m terrible at math). A lot of modern physics, at least the mathematical parts (which is a lot) is the same – whoosh.

However, I do try and keep up at least somewhat with the latest developments of the broader ideas and underpinnings of metaphysics and physics – especially physics, which is way more metaphysical than a lot of folks think it is. Philosophy of physics and the broad metaphysical ideas behind and under modern cosmology are just as important, and in my mind way more interesting, anyway.

I say all this to pick a fight with something Tim Maudlin says in his great book, ‘The Metaphysics within Physics,’ :

‘Metaphysics is ontology. Ontology is the most generic study of what exists. Evidence for what exists, at least in the physical world, is provided by empirical research. Hence the proper object of most metaphysics is the careful analysis of our best scientific theories (and especially of fundamental physical theories) with the goal of determining what they imply about the constitution of the physical world.’ (p. 104)

Now, it should be fairly obvious the issues here: the definition of ontology. Ontology is not the study of what exists, ontology is the study of being, or existence (you can be real anal and dispute whether or not those two words mean the same thing. I’m not going to). Being as such, not this or that particular thing that has being – or existence as such, not this or that thing that happens to exist. Being qua being. This is a pretty significant thing to get wrong.

A more concrete example: metaphysics studies how it is that change is possible (Parmenides, Heraclitus, Aristotle) and not this or that example of change (a chemical reaction, for example). What Maudlin does is to shift metaphysics from being the study of the absolute fundamentals of reality to a slightly more abstract form of empirical science, which analyzes various empirical theories. That isn’t metaphysics, that is just normal thinking.

In a nutshell, Maudlin’s scheme is that we derive metaphysics from physics, and further, ontology from physics. Our notions of existence comes from physics. Earlier in the same volume:

‘First: metaphysics, i.e. ontology, is the most generic account of what exists, and since our knowledge of what exists in the physical world rests on empirical evidence, metaphysics must be informed by empirical science.’ (p. 78)

I’m tempted to say that simply knowing what exists gives us no knowledge past bare sensory knowledge of particulars, which doesn’t really lead to knowledge of any kind, which is what Maudlin is setting out to do by analyzing various theories. But why restrict our knowledge of what exists to the physical, as Maudlin implicitly does? Twice above he says that whatever exists in the physical world is supported by empirical, or physical evidence. But that’s only trivially true – obviously, if something exists in the physical world, it will have physical evidence. But it doesn’t follow from that that the only notions of existence, or what exists comes from the physical world.

This seems to be a tangled way of thinking, which has its origin in Maudlin’s confusion of what metaphysics is. Now, as I said above, this isn’t my game. Analytic philosophy ain’t my thing, so it’s possible I’m quite wrong in my analysis. But what I see, in another nuthsell, is (a) a confusion of terms (ontology as the study of what exists), which leads to (b) the idea that our only knowledge of what exists is physical. To make ontology the study of what exists is to make metaphysics and ontology, as stated above, a slightly more abstract brand of empirical science.

Max Planck on Realism

 

 

‘Let us consider the facts of reality. Theoretical physics is based on the assumption that there exist real events not depending upon our senses. This assumption must in all circumstances be maintained; and even physicists of positivist leanings make use of it. Even if this school maintains that the priority of the sense data is the sole foundation of physics, it is yet compelled, in order to escape an irrational solipsism, to assume that there are such things as individual deceptions and hallucinations; and these can be eliminated only on the assumption that physical observations can be reproduced at will. This, however, implies what is not evident a priori, namely, that the functional relations between sense data contain certain elements not depending upon the observer’s personality nor upon the time and place of observation. It is precisely these elements which we describe as the real part of the physical event and of which we attempt to discover the laws.

Whenever we observe an event taking place in nature we must assume that something is happening independently of the observer, and conversely we must endeavor to eliminate as far as possible the defects of our senses and of our methods of measurement in order to grasp the details of the event with greater perfection. There is a kind of opposition between these two abstractions: while the real external world is the object, the ideal spirit which contemplates it is the subject. Neither can be logically demonstrated and hence no reductio ad absurdum is possible if their existence is denied. The history of physics bears witness, however, that they have played a decisive part throughout its development. The choicest and most original minds, men like Kepler, Newton, Leibniz, and Faraday, were inspired by the belief in the reality of the external world and in the rule of a higher reason in and beyond it.’ (Max Planck, ‘Physics and World Philosophy’ in ‘The Philosophy of Physics’, chapter 1)