We are responsible for our own irresponsibility, even if we refuse accept that responsibility.
If we do not choose our philosophy, a philosophy will choose us, and make us its host.
Perhaps that philosophy will tell us that we are socially determined, and that we are not responsible for how we are. But, for whatever reason, many such philosophies, hold others responsible. But these impersonal forces require us to act in certain ways… out of what? Justice…?
It is interesting how the very people who profess nihilism are the most horrified to be accused of immorality. They have no metaphysical support for morality, yet they take the “epiphenomenon” of guilt and shame far more seriously than those who give morality metaphysical significance.
It is hard not to suspect them of theoretical whistling in the dark — that they profess nihilism precisely because their belief in morality and their feelings of shame are too deeply felt and too undeniable — and acknowledging them as real and valid is too much to bear.
So the emotions are accepted as real but epiphenomenal, and the cause of the emotions is bracketed and shot into the noumenal vacuum.