What is causal asymmetry, and what does it mean for an effect to depend on a cause? The elusive nature of causal asymmetry and the problems with counterfactual accounts of causation have led some to abandon the very distinction between cause and effect, and others to postulate this distinction as a primitive not in need of justification. This contribution goes neither route, but instead offers an Aristotelian approach to causal asymmetry, according to which the possibilities which a particular entity can realize are both spanned and constrained by what is “in” the entity. Also, because the familiar cause-effect distinction may be the effect of our temporal perspective – as Huw Price has argued – I will not start from a consideration of instances of change, but rather of what I call “proto-change”: the existence of two states of an entity independently of the temporal order between them. Based on this, the argument proceeds through the following steps:
- The notion of being “possible with respect to” an entity is developed: an entity x is possible with respect to an entity y if it can be obtained from that, and only that, which is “in” y – i.e. y’s constituents, their kinetic or potential energies, and y’s total momentum. A proto-change of an entity depends counterfactually on the existence of an entity distinct from it whenever one of its states is not possible with respect to the other: for example, when one of the two states contains a constituent which the other does not, or has total momentum different from that of the other. Since this counterfactual dependence hinges on proto-change, rather than change, it is time-independent and does not fall prey to Pricean perspectivalism.
- A brief crash-course in local time, in particular the local distinction between “before” and “after” is given, an account which is based on the collection of states of a given object and on a characteristic asymmetry which appears on this collection.
- It is now possible to spell out how the time-independent counterfactual dependence (in 1) relates to temporal order (in 2): why do changes seem to depend on something that must be there before they occur (or at any rate, no later)? Let x be and entity and p a property such that x-without-p is observed to exist before x-with-p in local time. Based on the considerations in (1), I argue that an entity – call it y – distinct from x and having p must exist. Next, let W be a collection containing the states of both x and y, and let W1 be the state containing x-without-p, W2 the one containing x-with-p. It is shown that y-with-p cannot exist in W2, since this would lead to a contradiction, and must therefore exist in W1. By a further simple argument, this result is then extended to the case of n states of x, where n > 2.
In sum, we find that there is a robust counterfactual asymmetry independent of the direction of time, but nevertheless that which is necessary for a particular change to occur –that which we call its cause – must precede the change in local time.
This lecture was given on Thu, 1 July 2021, 10:50 (UK time) as part of the workshop Change and Changemakers in Ancient Philosophy. The workshop is a collaborative initiative of the Change and Changemakers Network (Siegen) together with the Mereology of Potentiality Project (Oxford).