What is it for something to ‘cause’ something else? This is a very difficult question to answer. No science or philosophy has yet really settled the question, in fact, and it remains a topic of serious debate now and for the future. We will leave that debate for the metaphysicians and focus on Aristotle’s version.
Aristotle’s approach was very down-to-earth. He said we should trust observation over theory and trust theory only if it matches up with the observable world. We should believe in what you can see, not in what you can imagine. And so if you want to understand something: look first, think after.
Adopting this approach, we can start to make some progress in answering the question: ‘What is causation?’ We need to look before we think. So when I look at, for example, a shoe, and I ask ‘what caused that shoe?’, ‘why that shoe?’, ‘why any shoe at all?’, I find I can say various things that explain why that shoe exists.
Firstly, I can point to the stuff that the shoe is made of: it’s made of leather, for example. If it were made of water, it wouldn’t be a shoe, but a puddle. So the ‘material’ that something is made of in some sense explains why that thing is as it is. Aristotle calls this the ‘material cause’.
But being made of shoe-like-stuff is not enough to make a shoe, it also needs to be arranged in the right way. If leather is cut into a strip and laid flat, with a buckle at one end, such that it fits around the waist, then it becomes a belt, not a shoe. So the ‘material’ also needs to be in the right arrangement, shape, or ‘form’. Aristotle calls this the ‘formal cause‘.
Thirdly, these things don’t just happen on their own, something (or someone) needs to take the material and arrange it in the correct form. In this case, we need some kind of shoemaker to make a shoe out of the raw materials. Or for natural phenomena, we need some kind of physical cause to exert itself on an object for it to change: rain needs to fall, or snow and ice needs to melt, in order for floodwaters to rise.
Aristotle calls this kind of thing the ‘efficient cause’, and it is the most intuitive notion of causation nowadays since it is the one most aligned with science. Most of science investigates efficient causes, rather than anything else, and we have all adopted that norm.
It is an impoverished norm, however, because there is one final type of causation that Aristotle finds that has not yet been mentioned.
A shoemaker takes shoe-type material and arranges it in shoe-type form, but why? Why does the shoemaker arrange shoe-type material into the shoe-type form? What causes them to do so?
Whatever answer comes to this kind of question will be Aristotle’s fourth and final notion of cause: what he calls the ‘final cause’. This is the purpose of the shoe. It’s the answer to the question of why the shoemaker takes the shoe-type material and arranges it into the shoe-type form. It’s because someone wanted to buy and wear some shoes! And someone wanted to wear shoes because they serve a particular purpose that the person values: in this case, to protect the feet and look super.
Aristotle says that each of the four types of causation are required in order to really understand what something is: you need to know a) what something is made of, b) the way that stuff is arranged or formed, c) the thing or process that formed it that way, and d) why.
This doesn’t just apply to people and their desire for footwear but also to natural phenomena. Stones roll down hills because a) the are made of stone-stuff (if they were helium they would float away); b) they are arranged in stone-form (if they were flat they would not roll); c) they were pushed, or had their position disrupted in some way (if nothing changes, they don’t move on their own…); and d) they have a natural tendency to ‘fall’. Aristotle didn’t have the benefit of knowing about gravity and such like, so expressed this natural tendency in terms of the stone having an innate purpose or drive or will to fall to earth, as it tries to return to its ‘natural place in the universe’. It’s as if the stone wants to fall. It’s not correct, of course, but we can forgive him for that. If you read this as a colourful way of describing the nature of a stone, he wasn’t so far wrong.
This, incidentally, is why the geocentric model of the solar system, which placed the earth at the centre of the universe, remained so entrenched for so long in human history. It has almost nothing to do with religious texts or the observation of the planets but everything to do with the fact that in Aristotle’s metaphysics, heavy things have a natural tendency to fall. And in the void of space, in which there is no up or down or left or right, where do things ‘fall’? They fall as far as they can, which is to the middle. Hence, the earth, the ‘heavy’ stuff, falls to the centre, and so the earth must be at the centre of the universe.
In order to reject that claim you would need to reject Aristotle’s metaphysics, and for the longest time there simply wasn’t an alternative metaphysics available. I like to think Aristotle would have been really pleased to find his metaphysics ultimately rejected on the basis of the observations of astronomers. As he said, we should trust theory only if it conforms to the available observations.
Read more: Think Well, Live Well: A Free Introduction to Philosophy
tobybetenson.com 