” The causal generation of a belief does not, of itself, detract in the least from its truth. My belief that I address a class at certain times derives from the fact that the presence of students in their seats is causally inducing certain images on the retinas of my eyes at those times, and that these images, in turn, then cause me to infer that corresponding people are actually present before me. The reason why I do not suppose that I am witnessing a performance of Aida at those times is that the images which Aida, Radames, and Amneris would produce are not then in my visual field. The causal generation of a belief in no way detracts from its veridicality. In fact, if a given belief were not produced in us by definite causes, we should have no reason to accept that belief as a correct description of the world, rather than some other belief arbitrarily selected. Far from making knowledge either adventitious or impossible, the deterministic theory about the origin of our beliefs alone provides the basis for thinking that our judgments of the world are or may be true. Knowing and judging are indeed causal processes in which the facts we judge are determining elements along with the cerebral mechanism employed in their interpretation. It follows that although the determinist’s assent to his own doctrine is caused or determined, the truth of determinism is not jeopardized by this fact ; if anything, it is made credible.”

Adolf Grünbaum, “Free Will and Laws of Human Behaviour”, American Philosophical Quarterly, 1971

HT: Justin Schieber