As I continue my journey reading Thomas Nagel’s book Mind & Cosmos I will pause here and there to make various observations. If it makes things more interesting, think of the book as a mystical land called Mindandcosmosia which we have come to by passing through a magical wardrobe. After squeezing between musty fur coats smelling of mothballs we suddenly hear the rustle of paper. Then black print emerges on a white page and we realize we’ve arrived in Mindandcosmosia!
We journey for several pages and then stop to rest on page 42 where we read:
“Major scientific advances often require the creation of new concepts, postulating unobservable elements of reality that are needed to explain how natural regularities that initially appear accidental are in fact necessary. The evidence for the existence of such things is precisely that if they existed, they would explain what is otherwise incomprehensible.” (Mind & Cosmos (Oxford University Press, 2012), 42).
I’m glad we paused on this page for it provides a very important and far-reaching observation about scientific enquiry. As Nagel observes here, novel entities can be posited on reasonable scientific grounds to explain that which would remain otherwise inexplicable. Sometimes it turns out that those posits do not in fact exist (ether, phlogiston). But in other cases their existence is ultimately vindicated. And in many cases, the entities themselves appear to be extraordinary to a staggering degree (think, for example, of the many worlds interpretation of quantum mechanics).
That which is true in physics is also true in metaphysics. Here too it is common practice to posit novel entities to explain extraordinary phenomena. Plato recognized this when he posited his theory of universals to explain phenomena like attribute agreement and abstract reference. And in that respect metaphysics (like philosophy more generally) is but a series of footnotes to Plato with an endless array of metaphysical postulates aiming to explain the extraordinary reality all around us.
There is no bigger question than this: Why does anything exist at all? After all, by any measure the universe is a contingent entity, one that might not have existed and thus one that does not explain its own existence. Consequently, if God — a necessarily existent agent creator — existed then he would explain what is otherwise incomprehensible.
So it is important always to keep in mind that appeal to God’s existence to explain the existence of the cosmos conforms to the same logic as the general inference to hypothetical entities that is regularly operative both in metaphysics and the natural sciences.
Now I think we better get moving. The sun is getting low on the horizon and we want to make it to the end of the chapter by nightfall. Believe me, you don’t want to be left reading this chapter in the dark.
