Consider: he got his umbrella because it was going to rain. The rain, which had not yet occurred, caused him to fetch his umbrella.
Or again: you are studying so that you will get a good grade at the end of the semester. Getting a good grade (in Aristotle’s terminology, a “final cause”) at some point in the future causes you to study now.
Other philosophers would argue, however, that it is the current expectation of rain which causes him to get his umbrella, and the current desire for grades which causes you to study. On this reading of the events, then, the causes do not at all lie in the future, but rather in the present.
Here we see yet another counter-intuitive understanding of “cause”: a cause which is simultaneous to its effect. Again violating the everyday understanding of causes as temporally prior to their effects, we see here causes which are logically prior but temporally coextensive to their effects. In Aristotle’s terms, these are often “material” or “formal” causes.
One of the most central of such cases is the question of what keeps objects in existence, or what keeps the universe in existence. Martin Heidegger wrote that one of the core questions of metaphysics and of philosophy is this: “Why is there something rather than nothing?”
In this sense, then, when we ask, “what is the cause of the universe?” we are asking not about what came before the universe in time, but rather what is sustaining the existence of the universe over time — what prevents the universe from simply disappearing altogether? This question lies on the boundary between physics and philosophy, and
The English philosopher C.D. Broad once noted that “the nonsense written by philosophers on scientific matters is exceeded only by the nonsense written by scientists on philosophy.”
Edward Feser (University of California, Santa Barbara) goes on to point out that, in this matter of writing about the cause of the universe,
from Aristotle to Aquinas to Leibniz to the present day, most versions of the First Cause argument have not supposed that the universe had a beginning in time.
So it doesn’t matter, when we are asking about the cause of the universe in this way, whether or not the universe had a specific beginning point in time or not. Even if the universe were to stretch infinitely back into time, that doesn’t change the question about what keeps it in existence. However, if we ask about what Aristotle calls the “efficient cause,” the universe’s beginning in time, or lack thereof, would make a great deal of difference. The efficient cause would be the last event prior to the effect itself which led inexorably to the effect.
As you can see, keeping track of these various notions of “cause” will be a lot of work. To muddy the waters still further, Feser writes about Aristotle, Aquinas, Leibniz, and others, that
their claim is rather that even if the universe were infinitely old, it is still the sort of thing that might in principle not have existed at all. That it does exist therefore requires explanation, and this explanation cannot lie in some other thing that might in principle have failed to exist, since that would just raise the same problem again. Accordingly, the explanation can be found only in something that could not have failed to exist even in principle — something that not only does not have a cause, but couldn’t have had one, precisely because (unlike the universe) it couldn’t in theory have failed to exist in the first place. In short, any contingent reality, like the universe, must depend upon a necessary being.
Even with four — or more — possible definitions of “cause” floating around, physicists and philosophers tend to agree on at least one principle: nothing can cause itself. But even that relatively obvious conclusion requires some complex argumentation, precisely because of the multiple definitions of causation. It needs to be shown true several times, for each of the several definitions:
The reason is that the very idea of something causing itself is self-contradictory: If a thing were to cause itself, it would have to exist prior to itself, in which case it would already exist and not need to be caused. (“Prior” need not entail “earlier in time”; the same incoherence arises even if we think of a cause and its effect as simultaneous, and interpret “prior to” as meaning “more fundamental than.”)
This skills is necessary for every rational thinker: to be good at distinguishing between what is temporally prior and what is logically prior. If we confuse those two, then we will make ourselves look foolish by means of the nonsense we write.
