Identity and Causality

Identity and Causality

It is generally supposed that an object cannot cause itself; causation only holds between distinct things. I will question this orthodoxy. The argument will take the form of nudging intuitions in the direction of the target thesis. The claim will be that every object causes itself (among other things); every object is an effect of itself (inter alia). The causal relation is (or can be) reflexive. I am both a cause and effect of myself. For any x, x causes x. First consider what Aristotle calls the material cause of a thing: the stuff that composes it. This is contemporaneous with the object composed, yet they are not identical objects (according to most views). I am caused (materially) by the cells in my body and the atoms in the cells: they produce me, constitute me, bring me into existence. We are not stretching the concept of cause very far in accepting Aristotle’s notion of material cause. There is more to causation than efficient causation by events spread out in time. We can also add causation by parts: a whole object can be said to be caused by its parts; together they produce or yield the object. The parts are the reason the whole exists, as the material of a thing is. But this doesn’t yet imply self-causation. How can we take the next step?

Propositions entail other propositions, but they also entail themselves—p implies p. So, entailment is compatible with identity; indeed, it might be viewed as the primary case of entailment. Propositions are self-entailing. But isn’t entailment a type of causation? It is productive, generative, a type of power; a proposition is a logical consequence of itself—a conclusion of which it is also the premise.[1] We could call entailment “logical causation”. The premise is sufficient for the conclusion; it guarantees the conclusion. Yet they are identical. But why not extend this way of thinking to objects? An object is sufficient for itself, a guarantor of itself, an upshot of itself. Like a proposition, it acts as a premise to itself as conclusion. If you know that x exists, you can infer that x exists: every object suffices necessarily for itself. Every object causes itself. It causes other things too, but among them is itself. It is a kind of limit case. Why not say this? Surely, it is reasonable to say that a property suffices for itself: if F is satisfied, then that property is satisfied. It will cause other properties to be satisfied, but it also causes itself to be satisfied—trivially, one might say. It is causally sufficient to satisfy the property of being red by being red—being red is enough to make a thing red, obviously. What is this “making” relation if not a type of causation? We don’t normally mention this case because it is so painfully obvious—it adds nothing to the conversation—but it is true nevertheless. If every object is trivially self-causing, we won’t have any need to assert that fact; but it is still a fact—as is the identity of every object with itself. Self-identity is a truism scarcely worth noting, and so is self-causation. If someone were to assert, “This table is a cause of itself”, we would reasonably (and sarcastically) respond, “So, what else is new?”

If your intuitions are now moving in the desired direction, let me politely nudge them further. Can’t we say that type identity is compatible with causation? If an object replicates itself, producing an identical copy, doesn’t it cause the same type to exist elsewhere? True, there are two tokens, but doesn’t the type do the causal work? The type causes itself to appear elsewhere. When a cell divides, the new cells come to have the type they have in virtue of the type of the original cell, but now in a different place. The causal relation operates at the level of the type, and it is the same type in another location. The type is causing an identical type in another token. Types cause themselves to replicate. We say, “This type came to be because of that type”, referring to two token instances of the same type. Now consider identity through time: an object at one time causes itself to have certain properties at a later time—say, in the development of an organism (e.g., a butterfly). The object is causing a change in itself not in some distinct object: x at t1 causes x at t2 to be F. The causation is reflexive and cross-temporal. There is no conceptual problem about this. So, why not allow that an object can cause itself at a time? It can cause itself to be F at a time, to exist at a time, and to be itself at a time. To be sure, it can’t efficiently cause these effects, i.e., by being antecedent to itself, but not all causation is efficient causation. Once we loosen the concept up a bit, we can see our way clear to self-causation. I am the reason for my own being—not the sole reason, but a reason. I am me because of me: how could that fail to be true? I don’t go around excitedly announcing this to all and sundry, because it is insultingly obvious, but it is a metaphysical truth (like “numbers are objects” or “events happen”). It is puzzling that Aristotle never included this in his list of causes, but he could have—call it “identity causation”. Just as we say that every object is identical to itself, so we can say that every object causes itself. Neither proposition will make the evening news (“Scientists have discovered that not only is every object self-identical but every object is self-causing. For more on this over to…”).

The metaphysics of causation has long debated the extension of the concept cause, with narrow and wide interpretations proposed. For some reason, so-called efficient causation (isn’t all causation efficient?) has recently held pride of place, with Aristotle’s four types reduced to one. I am suggesting we up the tally to five. In time it may even seem to people as if this was the right place to start: the first and most obvious category of causation is that between an object and itself; everything else is an extension of that basic idea. We thus have identity cause, formal cause, material cause, teleological cause, and efficient cause—in that order. The most internal cause is identity cause: causation begins at home, as a relation between a thing and itself. And isn’t it nice to think of oneself as one’s own cause? I am literally a self-made man (and I did it my way).[2]

[1] See my “A New Metaphysics”, “Causal and Logical Relations”, and “Because”.

[2] It is customary to think of one’s parents as the proximate cause of one’s existence, but on the present conception there is another link in the causal chain (or structure)—you yourself. And notice that you are indubitably sufficient for your own existence, but nothing else is—the causal chain might have been interrupted at any point before your glorious self popped into being. Only you guarantee you. Granted you are the product of other things too, but at least you play a causal role in bringing about your existence. Everything, in fact, is a self-caused cause—and effect.