Causation has long engendered deep and passionate discussion. This springs from our innate desire to know. We want to know why and how things are the way we observe them. Why do unimpeded objects always fall back toward earth when we throw them up in the air? Why does the universe exist? What explains variation and complexity in biological species? Why does my child think it a crime against humanity to sleep at night? Countless other questions could be raised as examples. But is causation interesting in itself? Metaphysicians certainly think so. Few others, including philosophers, take much notice. I think most people give perhaps only a passing thought to causes because they unreflectively accept a very narrow, and highly problematic, view of causation. They take temporally sequenced events as a de facto explanation of causes. Not only is this position untenable, it is (worse) completely uninteresting. In what follows, I will offer a few brief thoughts on why this is the case.
When most people think of A causing B, they think that A moved B from point 1 to point 2. Or that A made B from a collection of raw materials, so A caused B. Or, if B regularly follows A, then A is the most likely cause of B. Causation is typically bound up with some type of temporal succession of events. Ceteris paribus, if C is always observed to follow B, and B follows A, A is thought of as the probable cause of C.
The preceding description of causality is precisely what David Hume had in his gunsights. Such events, loose and separate, as it were, cannot really tell us anything. We cannot empirically observe “causal powers” and we have no logical contradiction in B not following A (no matter how regularly it does), so causality is committed to the flames. Sure, we could say that A caused B, but there is no state of affairs where A is causing anything, whether it is B, bicycles, or bananas.
If we buy into the strictly temporal/sequential view of causality, then it is very difficult to demonstrate why Hume is wrong. Sure, his conclusions might be intuitively absurd. But, as Hume would no doubt rebut, “so what?” Intuition does not falsify his position nor establish causality (so understood). Other responses to Hume, such as appealing to possible worlds, counterfactuals, and so forth do not, it seems to me, really get at the heart of Hume’s argument. In the end, I think it is very difficult to respond to the portly Scotsman without appealing to an Aristotelian conception of nature and causes. Most contemporary philosophers will not make this move and will largely leave causation neglected in the corner of a dark room. The Stagirite looms outside, not being invited to the party at all.
The most interesting questions, such as why and how, are answerable on Aristotle’s view. And satisfyingly so. We seek explanations and we find them. Take a very simple example; my tan floor tile. Not much interesting about that, right? But what if we started with a few questions that we could ask about anything in our daily experience? Like why is the floor tile here? Am I the cause of the floor tile under my foot? After all, six months ago, I bought it from the store, mixed the mortar, cut, and laid the tile on the floor. Yet, on an Aristotelian view of causation, it really cannot be wholly said that what I did previously is the cause of the tile under my foot.
We could perhaps say that I was the cause of the tile getting where it is at a time in the past. But why is it here right now? Why does it keep the qualities it has, like color, size, weight? If we really think about it, there are myriad other factors involved, such as the subfloor, house foundation, earth, and all the other laws of physics that must hold constant for the floor tile to be under my foot at any given moment. The reason the tile is under my foot right now is not explainable in any interesting way by the fact that I transported and laid it. Nor does the metaphysical interest lie with the tile manufacturer. When we are concerned about causality, the less relevant thing is the preceding event in time. This is because the prior temporal event does not really answer the basic metaphysical questions we are after. We want to know why this and not something else. The floor tile could, in principle, not be under my foot right now (even if it was in the prior second). We even might put something like this back to Hume. In any event, the temporal sequence might be metaphysically interesting in some way to us, such as understanding the process by which one might lay floor tile, or how floor tile is made and successfully transported. Yet there would be underlying metaphysical questions for each of these events that would necessarily force us into a deeper inquiry.
What if we just stopped at the manufacturing of the floor tile? Is there anything about this that assures it will stay the same shape and color on the way to my house? Here, again, we could resort quickly to various laws of physics and chemistry. But, what about those? Surely these physical laws and chemical compounds held constant during each moment of my journey. At any moment of investigation along the way, I would have the same question. Why this, and not that? Aristotle gives us answers. Formal, material, efficient, and final causes each represent actualized potentials. Thus, we can understand the cause(s) of the floor tile in a multifaceted way. We need not stop with a sequence of events. Such a sequence is accidental to the tile itself as it stands (or is stood upon) right now.
If we are only focused on causality in terms of temporal events, then we will ultimately lack sufficient explanation for anything. To take another example, as I look out into my front yard, I see my son’s Big Wheel. I could say the cause of the Big Wheel in my front yard is that my son left it there yesterday afternoon. Maybe I could press on and ask how the Big Wheel got to my son. And then we could talk about the plant, factory, workers, shipping, etc. Ultimately, we would just be explaining each thing by appealing to the prior event ad infinitum. However, this does not really tell us much. Why not ask why the Big Wheel exists as it does? Why does the Big Wheel not spontaneously melt or turn into a pumpkin? Why not ask why the Big Wheel does not collapse into non-being? These are metaphysically interesting questions. Such questions help us understand reality.
We can explain the existence of the floor tile or the Big Wheel in Aristotelian causal terms in a layered analysis, going so far as we desire in hierarchically ordered causes until terminating in Pure Act. Or, we can stop with a more basic, coherent, and robust understanding of the physical object; existing as a substance with various accidents, having a certain a form, material, efficient, and final cause(s). In any event, we can have a deep metaphysical conversation starting with the simplest objects. I am not aware of another system from which such a fruitful discussion can spring forth. This is especially true of efficient causality, which should be conceived as much more than the mere bringing forth of something from one state to another as most artifactual examples entail. This is, of course, one of the many benefits Aquinas brings in his Aristotelian-grounded philosophy and not an incidental reason why one should consider moving beyond thinking of causes merely in temporally sequenced terms.