Let’s assume we all agree that nobody ever decides how to act on the basis of a moral theory. This view is called moral particularism, and in my opinion it’s woefully underrated in current ethical philosophy.
At first glance you might object that, when asked why we perform certain actions, we generally respond with an argument from a moral theory. But how we talk about our decision-making process is mostly bullshit. A 1977 article by Nisbett and Wilson, Telling More Than We Can Know: Verbal Reports on Mental Processes, concluded that our introspective access is “not sufficient to produce generally correct or reliable reports”, and that we usually make up theories to explain our haphazard thought processes. In real life we base our ethics off emotion and empathy instead of ethical theories.
You might also object on educational grounds. When a child asks us if it’s right to take his friend’s lunch, nobody responds: “Well, ethics is complicated and I can’t give you an ethical theory that holds in all instances. Rely on your conscience and it will guide you.” Instead we tell them it’s wrong to steal. But what are we really doing here? I contend that we’re not teaching a child a moral rule; instead we’re doing a number of things. We’re providing a moral example in our not-stealing selves. We’re suggesting certain considerations that might be morally pertinent in this instance. And so on.
Why am I fielding objections to moral particularism in a post titled Why Theorize About Morals? Because these two objections point the way towards a discussion of moral theory that’s compatible with the idea that theory doesn’t guide our actions. If we want to hit a baseball a long way, we don’t study aerodynamics or physics, we practice baseball. But if we want to explain why a certain baseball swing is more effective, we need to go into biomechanics and physics! The batter doesn’t care why a swing works, only that it does, and the moral actor qua actor doesn’t care why an act is right, only that it is. But scientists and philosophers are going to be interested in those ‘why’ questions.
In short: just because talking about morals isn’t helpful to people who want to act morally doesn’t mean it’s not an interesting field of study.
(It’s also worth noting that what I’m doing now is “talking about morals” – so moral philosophy might indeed be useful as a path out of moral theorizing, in the same way that anarchism is useful as a path out of politics.)