If ontology is a study of being (reality) and epistemology is a study of knowledge, then what would be considered a study of 'doing', or 'action'? I am interested because a statement was made to me recently describing a set of dictum's not as a prescription for 'doing' but a prescription for 'being'.
Let's start simple. There is a branch of philosophy called precisely 'the philosophy of action'. The larger branch to which this belongs is the philosophy of mind or (a less common term these days but the same thing) philosophical psychology.
Typically the philosophy of action concentrates on human action and poses such questions as : 'what makes an action intentional' ? 'How does a voluntary action differ from an involuntary action ?' 'What type of reasoning lies behind intentional action ?' 'Can we do intentionally what we believe is a wrong course of action ?' This is only a sample from a long list but the list is often defective. At this point we can delve a little deeper.
How so ? Because there is no conceptual necessity to restrict the philosophy of action to the philosophy of human action. Yet this is precisely the characteristic scope of philosophy of action. But surely a monkey or a hippopotamus can act. It may not be able to represent the world as humans do when they act intentionally from beliefs. To deny that they act and that we can conceptualise their actions seems mere dogma.
Another point is that traditionally Western philosophy has centred on human beings as knowers. What can we know ? How can we know ? This has given epistemology a priority over the philosophy of action. Our relation to the world through action, however, may be just as important, if not more so, than our relation through knowledge. What would we know if we never acted ?