Commentary: freedom and function.

While the question of whether our actions are determined or are the result of free will is a deep one in philosophy, it does not need to be answered for forensic psychiatrists to give evidence in court. As Stephen Morse has pointed out, the absence of free will is not named as an excusing condition. The insanity defense, for instance, requires proof of functional impairment, to which psychiatrists can usefully testify. Of the approaches available to determinism, my own preference is that of Herbert Hart: until we know that determinism is true, we will continue to prefer a system that requires persons to have made proper choices to act as they did before we hold them responsible. This seems to resemble Dr. Felthous' preferred option, that mentally responsible choices are choices made in the presence of a relatively natural ability to have decided otherwise.