What is the cause-and-effect relation like, precisely? What happens, for example, when a brick goes through a window, and the window shatters? Since Hume’s time, most philosophers have taken causation to be a relation between two events. They would say that, strictly speaking, the brick does not cause the window to break. Rather, it is the brick’s moving that causes the window’s breaking. This seems to make sense, but I want to suggest another way of thinking about things.
First, let me be more precise about what events are. An event is:
- an entity’s coming into existence or going out of existence; or
- an entity’s gaining some property, losing some property, or simply having some property.
The last alternative on the second line is sometimes called a state in contrast to an event, but here I don’t think the distinction is important. (In this definition, I talk about entities having properties, but I don’t think properties actually exist: they are abstractions that we use to describe the different ways in which things can exist or resemble each other.)
An event is a rather ephemeral thing to have the power to affect reality. Events are not exactly abstract objects, but they are also not things that can exist on their own: events depend for their existence on the things that they happen to. The entities that events happen to are more fundamental than the events themselves. And when I consider it, it seems that it is the things that exist in the world around me, not the events that happen to them, that have the capacities and dispositions to cause changes in reality.
So I would say that it actually is the brick that breaks the window. The brick, rather than the event of its moving, is what causes the window to break. And complementary to that, the brick’s moving is the situation in which its capacity to break the window is realized. So we can say that the window breaks because the brick was moving in such a way (giving an explanation for an event), but what causes the window to break is the brick itself (citing the cause of the event).
My view, then, is that causes are concretely existing entities, and effects are events that happen to those entities. These kind of entities have certain causal powers or liabilities, capacities to affect or be affected by other entities. Powers and liabilities are paired: every causal power entails that something has a causal liability to be affected by that power. And those powers or liabilities may require that certain events happen in order to be realized.
(Note: I don’t have a precise term for the kind of entities that can be causes and that events can happen to. But what I have in mind are things like bricks, windows, photons, people… in other words, the kind of non-abstract things that come to mind most readily when you think about what exists.)
My view about the nature of cause-and-effect is mostly based on intuition, I’ll admit, but it is the view that makes the most sense to me. It coheres with my belief that it is the things in the world that push and pull on one another, not the events they are in. It readily incorporates my powerful intuition that I cause things to happen in reality: I am writing this blog, I am pouring this glass of water. (Writing is thirsty work, you know.) And it grounds cause-and-effect relations in the capacities of things that exist in the world around us.
One argument against this view is that you can’t properly form causal chains if causes and effects are not the same kind of thing. The usual view is that both are events, so that one effect can become the cause of another effect, and so on.
But you can still form causal chains on my view: the entity that an effect happens to can become the cause of another effect, and usually we talk about chains like this when the first effect put that entity into the situation where its capacity to cause the second effect was realized. So I don’t see anything wrong with thinking about causation in this way.
What Kinds of Causation are there?
What kinds of causal powers and liabilities exist in the world around us? I think we can put cause-and-effect relations into three (maybe four) categories.
First, there are deterministic causes. These are the kind that we are most familiar with from the basic physical sciences: a billiard ball strikes another billiard ball and sets it in motion; a sugar cube dissolves upon being stirred into a cup of coffee. In these kind of cases, given the circumstances, no other outcomes were possible. When something is caused deterministically, the effect is completely fixed by the situation that the cause happens to be in.
Second, there are indeterministic causes. Interpretations of quantum mechanics differ on whether this kind of causation is a fundamental part of reality or not; some would say that the laws of physics do completely determine the future state from the initial state, others say that they only determine probabilities that different future states may be realized. But an example of indeterministic causation would be atoms being caused to decay by the interactions of their underlying quantum fields, without the cause determining exactly when it decays.
When something is caused indeterministically, the effect is not fixed, but is a random outcome from a range of possibilities. What may be determined is the range of possible outcomes and the various probabilities for them.
So causes can be deterministic or indeterministic; I appear to have exhausted the options here. Is there a third category? I think we have, or at least seem to have, intimate experience with a third kind of cause: self-deterministic causes. This is the kind of causation that is going on when we act by our own free will and choice. If, for example, I am sitting on a committee and I raise my hand to vote on some motion, I cause myself to raise my hand. But I wasn’t determined to do this by my environment, and it wasn’t just a random effect that happened to me. (At least, that is the way it seems.) Rather, I had certain reasons for raising my hand, and I acted on those reasons.
Deterministic causes, and indeterministic causes where the effect is a random outcome from a range of possibilities, may both be thought of as passive kinds of causation. The entities that stand in these kind of cause-and-effect relations are not active participants in the events of nature, but rather are passively subject to the forces that arise from whatever situation they are in.
In self-deterministic causation, on the other hand, the cause is an agent, someone who acts for reasons, goals, or purposes of their own. Self-deterministic causation is inherently teleological, that is, purpose-oriented. And usually, self-determined causes (in the way that I am presenting them here, where the cause is an entity and not an event) are explicitly thought to not be determined to cause the effect that they do by the situation that they find themselves in. These kind of causes could also be called active indeterministic causes, contrasting with the passive indeterministic causes I described earlier.
There is, of course, serious philosophical debate about whether there can be such a thing as a self-determined cause whose effect is also determined by the situation it finds itself in (active deterministic causes, the maybe-fourth category I mentioned above), whether actions that are so determined can be counted as free actions, and just what the relevant sense of being free is that is necessary for assigning moral responsibility. And there is serious philosophical debate about whether self-deterministic causation is possible at all.
I will weigh in on those matters at a later time, as I continue to explore the nature of reality. For now, I will just say that if self-determined causes do exist, reality is very, very different than it would be if they did not exist.
I say this because it is generally thought that physics leaves no room for self-deterministic causation. Electrons and photons do not have goals or purposes of their own, and they do not exercise any active power over each other; the entities of physics on their own are subject only to passive causation. And if apparent instances of active causation, such as our very familiar activities of choosing to walk here or there, or to speak certain words, or to read and think about certain topics, could all be reduced to the motions of fundamental physical particles, then active causation, and agents themselves, never really existed in the first place.
Following that reasoning in the other direction, if self-determined causes do exist, then physical reality is not all there is. So this is an important topic to consider, and I will be coming back to it a few posts down the road.