The Pesky Inevitability of Metaphysics

On the dangers of epistemic austerity

Giorgio de Chirico, 1917, Il grande metafisico (The Grand Metaphysician)

Note to Boston-based readers: My in-person reading group will soon be starting a reading of Spinoza’s Ethics some time in early October. If you’ve read much of this blog you know Spinoza is probably the philosopher I’ve spent more time on than any other, and I’m looking forward to reading his work carefully and trying to gain a better understanding of it with a group of smart and engaged people. If you’re in the area and free on Thursday evenings, email lowlybookclub@gmail.com to let me know you’re interested. The group is informal and space is therefore limited for practical reasons, but we’d like to involve a few more people.

The more philosophy one reads, the more it seems cyclical rather than linear. It seems to be the fate of all philosophers to repeat, albeit in new vocabulary, cultural milieu, and perhaps logical trappings, the ideas of some philosopher from centuries, if not millennia earlier. The picture that emerges is that there is no innovation in philosophy so much as an oscillating variation in emphasis. Logical Positivism was no exception, and serves as well as any of its prior iterations as a demonstration of the problems with eliminating metaphysics as a branch of study.

Logical Positivism (or logical empiricism, or neopositivism, or whatever you want to call the central claims attributed to the Vienna Circle) was a movement in 20th century philosophy which held that all statements with literal significance, and therefore truth value, were statements which could either be verified by observation, or were logical tautologies which were true merely by definition. This scraping of the philosophical edifice down to its frame was extraordinarily violent, like the scrapings of skeptics that had come before it, and reduced philosophy mostly to a study of the linguistic tools by which we could understand scientific discoveries, and a means to guard the walls and ensure nothing other than scientific discovery might be mistaken as actual knowledge.

Positivism amounted to the crest of a wave of anxiety about metaphysical speculation in philosophy, an existential crisis about the field’s legitimacy, a resurgence of an earlier wave made by David Hume and his worry that philosophy seemed to be continually mired in disputes over metaphysical notions which it had no means of resolving. These include questions like, Is there one substance in the world, or many? Are things physical, or mental, or both? Is there an incorporeal God? Is there such a thing as change? What is virtue?

These questions, Hume observed, had never been resolved, and he believed they could not be resolved, because the mistake had to do not with the reasoning that led to differing answers, so much as with the questions themselves. Because they dealt with matters that couldn’t be resolved through observation, they couldn’t be resolved, period, and were therefore simply bad questions to ask, ones which could only yield meaningless and hallucinatory answers.

It is this which we find re-affirmed in Positivism two centuries later, which set as its criterion for truth (at least as it was formulated in A.J. Ayer’s Language, Truth, and Logic) the “Verification Principle,” which was really nothing more than a resurrection of Hume’s fork, which divided all knowledge into ‘relations of ideas’ and ‘matters of fact’, or ‘analytic a priori’ and ‘synthetic a posteriori’ categories. We either know a proposition is true or false because it is so by definition, or because of some observations we can make about the world. If we can’t even in principle make an observation which would either confirm or disconfirm the proposition, then any statement conveying that proposition is not merely speaking about a world we lack the faculties to understand; it is literally meaningless.

The problem was the same for the Positivists as it was for Hume-there is really no way to make verification work without either rendering it trivial, or so epistemically conservative that it makes virtually all knowledge impossible. Worse still, there is no way to verify the verification principle by its own criteria. And this is unsurprising, since the main objects of the verification principle, truth and falsehood, are clearly abstract entities beyond experience themselves. Nor can we verify that observation itself is conveying the world to us as it really is, not only due to the basic problem of induction, but because our powers of observation are the product of evolution, which someone using observation itself as the sole standard for truth therefore ought to regard as unreliable. Ayer himself, one of the most important exponents of Positivism in English philosophy, joyfully disparaged his own earlier position in a way only a great philosopher could, proclaiming that the main problem with Positivism was that “nearly all of it was false.”

Epistemic belt-tightening like that of the Positivists, excessive and frankly boring as it may be (and all flavors of Empiricism are stultifyingly boring, almost as a matter of doctrine), is a natural and appropriate reaction to the strong tendency of philosophers to let their metaphysics run away with them. Whether it be Thomistic philosophers plucking metaphysical explanations of trinitarianism, transubstantiation, and angels out of thin air; or German Idealists devolving, within two generations, from Kant’s attempt to present a sober and conservative metaphysics to the explosion of revolutionary ideologies generated by the Young Hegelians; or Leibniz claiming an infinite number of propositions in the essence of each thing coordinated in perfect harmony with an infinity of propositions in every other; it seems almost inevitable that if you give the philosophers an inch of the non-empirical, they will generate seemingly anything. And if a truth-seeking mechanism, even when manipulated by the genius of a Kant, Leibniz, or Hegel, can generate a wild diversity of outcomes, this suggests the mechanism is broken, and desperately needs reining in. Empiricists and skeptics are surely right to do this from time to time.

The problem is that they inevitably throw the baby out with the bathwater. Metaphysical speculation is exceedingly natural and not obviously illegitimate (after all, people did it without a second thought for nearly two millennia). Indeed, the repeated failure of verification as a criterion of truth is evidence that it’s unavoidable if we want to distinguish between true and false at all. We apply abstract reason to practical problems, and we find that it does in fact produce the desired results in the world as a fairly standard fact of day-to-day life. Indeed, it has repeatedly happened in the history of science that abstract mathematics that had already been invented long before was adapted for scientific applications, such as the use of parabolas in the development of optics, or the use of differential geometry to develop the theory of general relativity. It is impossible to avoid the resulting temptation, that the application of reason to topics other than quantities and geometrical figures could yield similarly accurate results, although empirical verification may not be available, and, yes, is even in principle impossible. Indeed, exactly the same process of reasoning that produces parabolic and differential geometry can also lead to higher-dimensional geometries that are surely impossible to replicate in extended 3-D space. If there is not, in principle, any end to pure mathematics, why then would there be any end to metaphysical speculation? As Michael Della Rocca argues in his 2010 paper defending the Principle of Sufficient Reason, if we accept that something must have an explanation, it’s very hard to see when or how we could say, in any principled, non-arbitrary way, where that chain of explanation must stop. This doesn’t mean that we should be so certain of unverifiable claims that we would stake our lives, or especially the lives of others on them, but we are certainly not unjustified in giving them some credence.

Furthermore, all the very good motivations for epistemic belt-tightening notwithstanding, it is very difficult to see how philosophy can yield any useful doctrines about ethics or politics if it cannot reach conclusions about questions like the nature of God or the relationship between mind and body. If this is the case, then I really doubt that philosophy is actually of almost any value, except perhaps as a brief epistemological preamble to science. This is admittedly not nothing. But while we can probably never know whether or not this is actually the case, it seems like people, who turn to philosophy for guidance and a sense of transcendent orientation and purpose that is less arbitrary than that offered by religion, at the very least need to be able to believe that the transcendent claims of metaphysics could be true in some meaningful sense in order to live happy lives in stable, free societies.

One can’t help but wonder whether the retreat from metaphysical speculation in philosophy has partly motivated the migration of intelligent young people back into religious dogma, and perhaps with it, of liberalism back into some flavor of authoritarianism. It is surely true that people strive towards something transcendant or beyond the bounds of common sense, and I believe this striving is the underlying aim of all science, ambition, art, and faith. Philosophy is a striving for knowledge of that which is in principle unknowable, and to deny that we can make any progress towards it in philosophical study and the use of reason in general seems to be like if music as a field reached the conviction that affecting an emotional change in the listener is impossible. Someone who had reached such a conclusion would surely have lost any reason to pursue the art any further.

But people will find a way to strive towards transcendance somehow. They will transcend through drugs, they will transcend through ghost stories, they will transcend through conspiracy theories, they will transcend through checking their Twitter notifications, they will transcend through the church, and they will transcend through destroying those they hate. Nature abhors a vacuum, and whatever ground reason cedes, something that is not reasonable will take its place. In the process, we become passive recipients of whatever received nonsense makes us feel good, which was after all what the Positivists sought to avoid. On that count, at least, they were surely right.