Nietzsche's break with Schopenhauer rests on precisely this point; it is a matter of knowing whether the will is unitary or multiple.

As for being responsible or irresponsible, we don't recognize those notions, they're for policemen and courtroom psychiatrists.

A tyrant institutionalises stupidity, but he is the first servant of his own system and the first to be installed within it.

Either it is the fold of the infinite, or the constant folds [replis] of finitude which curve the outside and constitute the inside.

It is not the slumber of reason that engenders monsters, but vigilant and insomniac rationality

The shame of being a man - is there any better reason to write?

Nietzsche's break with Schopenhauer rests on precisely this point; it is a matter of knowing whether the will is unitary or multiple.