People speak not only of the actions of human beings and other intelligent animals but also of the actions of inanimate objects such as acids and waves. The philosophy of action, however, is not directly concerned with the actions of inanimate objects. Its primary subject matter is intentional action. Two questions are central in the philosophy of action: What are intentional actions? And how are intentional actions to be explained? An adequate answer to the first question would enable one to see how intentional actions differ from everything else—including the actions of acids and waves, nonactions, and unintentional actions. A successful answer to the second question would provide one with the theoretical machinery to use in explaining why you are reading this entry and why the author wrote it.

Intentional Action and Individuation

According to an attractive causal theory, intentional actions are, in one important respect, like...