Compatibilism is a philosophical attempt to rescue personal responsibility from determinism. The idea, now fashionable in scientific and philosophical circles that, thanks to an ultimately deterministic macro-universe, libertarian free will is an illusion. The libertarian part is important because compatibilists are so named precisely because they claim that we can be responsible for our acts even in the absence of our capacity as agent to initiate novel physical chains of events (through control of our bodies which are indisputably physical). Initiation is the key here. As Lowe points out (“Personal Agency” 2004) when I elect to raise my arm it is my brain and its physical connection to physical nerves, the nerves to muscles, etc. that actually controls the physical motion of my arm. That is the micro motions of my arm, the exact speed with which it goes up, exactly how high, and at exactly what angle, etc are all controlled by a physical chain of multiple events in my nervous system coupled with the capabilities of my muscles. What I do as an agent is initiate this process by choosing to raise my arm in a general sense with such and such a force, in so and so direction, etc. In order to be libertarian, that choice has to be theoretically prior to any physical causation. I might raise my arm because I want to ask a question of a lecturer, but that reason is not the cause of my arm’s going up because I could just as easily have chosen not to ask a question at that moment. Nor does any activity in my brain outside my conscious control force me to raise (or not raise) my arm. For libertarianism to be real then, there must be some agent who has the power to “initiate physics”. It is exactly this power that is denied these days by a large number of scientists and philosophers.
I think compatibilism has problems on several levels but before I get to them let’s look at what compatibilism says. The basic idea here is that if some act of mine is not coerced by an external agent, then I remain responsible for it even if in the end the act was foreordained by some prior set of physical events ending in my brain and thus the act itself. If someone puts a gun to my wife’s head and threatens to kill her if I do not rob a bank, then I am not responsible in any full sense for robbing the bank. If on the other hand there is no gun to my wife’s (or my) head then I am responsible for robbing the bank even if that act was not a libertarian choice but rather the culmination of prior physical causes, that is brain activity. Notice however the key requirement for agent coercion in the compatibalist view. Suppose I am far from home, tired, cold, and have no money. I choose to break into what appears to be an unoccupied house merely to get warm and spend the night. Surely I am responsible for that act. Now imagine that it isn’t tiredness that drives me but a hurricane from which I wish (naturally enough) to take shelter, so I break into the same unoccupied house. Neither act involves agent coercion and any court would find me guilty of breaking and entering in either case. In the latter case, the court might forgive my act because it would be reasonable for me to believe that by remaining outside the hurricane threatened my life. But I remain responsible for the act. By contrast if a man (an agent) put a gun to my head and threatened to kill me if I did not break into that house I would not be judged responsible for it.
So lets have a look at this… If I am coerced into doing something under threat of death from another agent then I am clearly not responsible for that doing in any normal sense. But given the assumption that libertarian free will is an illusion, why does agency coercion make a difference? Presumably if not coerced I would not rob the bank, but what about the agent who coerced me? Supposing he was not himself coerced into putting a gun to my head, a court would say he was responsible for that act. But since libertarian free will is an illusion, his behavior was determined in some sense by his brain in someway over which he had no prior control. Indeed even if I was not coerced, I too had no choice in the matter because my behavior also was determined, if not by coercion then by events in my brain and their causes and their causes and so on all the way back to the big bang — or at the very least to my birth.
The difference between the gun to my head and the hurricane is that in the latter case we might presume I had some alternative than breaking and entering. A hurricane might kill me, but then it might not. But the same thing cannot be said concerning brain events. The universe may not be an agent, but its deterministic imposition is even more sure in its result than a gun to my head. I might, after all, fight off an armed man, but I cannot fight off the causal outcome of a brain state over whose particulars, the result of a long chain of events, are beyond my control.
In effect I am an automaton differing from a more conventional automaton only in degree and not in kind. Even today we can build highly adaptive automatons so our appearance of adaptiveness is hardly a counter argument. The difference is only that the conventional automaton’s fixed state, its starting state, goes back only as far as when it was first turned on. Mine goes back at least to my birth, and if we take the metaphysical implications of the sort of determinism we are talking about seriously, all the way back to the big bang.
Returning more directly to compatibilism, besides the matter of prior determination, by a coercing agent or the universe, there is the problem it presents for the notion of agency itself. Libertarian free will is dismissed on the grounds that there is nothing in physics that supports it. But the same can and has been said about mind, consciousness in general, and the experience of agency, our subjective awareness of a self that appears to have an internal arena (consciousness) and the power of libertarian free will. There is nothing in physics that supports those either! If purely physical processes can cause to emerge a subjective that appears from the experiential inside to be non-material, there is nothing in physics that would permit that epiphenomenal entity to have any downward effect on physics. Physics might recognize an utterly illusory agent (although the ontological status of illusions is problematic), but the illusion cannot be permitted to effect a change in physics. If it could, then any such effect might in fact be the freely chosen act of an ontologically genuine (given that an illusion cannot cause physics) agent, the very notion rejected as being impossible.
How can an agent coerce me if the agent is an illusion and cannot affect physics? A man with a gun to my head is merely another automaton. Of course I will follow instructions and rob the bank because an additional layer of coercion has been added to that which determines my choices anyway. If there had been no gun to my head I would not rob the bank, but that course too would be the outcome of a deterministic chain. There is nothing in physics that prevents the behavior of one automaton from becoming part of the input to which another automaton adapts but either way, there is no agent acting, only a zombie (albeit a complex zombie) body, so the relation of agency to compatibilism is incoherent. Without libertarian free will the agent is no different from the hurricane. By denying libertarian free will and resting compatibilism on the presence or absence of a coercive agent, philosophers are resting a doctrine of responsibility on a redundant illusion. I am coerced by circumstances no matter what I do and no matter if there is an “agent-automaton” present or not.
If libertarian free will is genuine then we are already responsible; we are agents of our will and must own our acts. We don’t need compatibilism. But if libertarian free will is an illusion, no compatibilism will recover our responsibility because (1) the very notion of “agency” becomes problematic, and (2) even if the agent notion were somehow coherent, its behavior is determined at some level with or without the presence of a “coercing agent”.