Buridan holds that the proper subject of psychology (i.e., the science undertaken in Aristotle’s De Anima) is the soul, its powers, and characteristic functions. But, on his view, the science of psychology should not be understood as including the body nor even the soul-body composite as its proper subject. Rather its subject is just “the soul in itself and its powers and functions insofar as they stand on the side of the soul". Buridan takes it as obvious that, even thus narrowly construed, such a science is possible. To the extent that this science includes the human or intellective soul, however, Buridan’s claim regarding its possibility is far from obvious. After all, like most of his contemporaries, Buridan takes the human soul to be immaterial. Thus, he readily admits that “the intellect cannot be sensed” and its operations are likewise inaccessible to the senses. Yet, on Buridan's broadly empiricist theory of knowledge, all (human) knowledge, including knowledge of the intellect or intellective soul, takes its start in the senses. How, then, is a science of the human soul possible? What is the nature or source of our knowledge of the intellect? In this paper, I reconstruct Buridan's answer to these questions.
My discussion divides roughly into two parts. In the first, I set out the main elements of Buridan’s account of how we come to cognize the intellect, focusing on what he says about the genesis of our concept of the intellect. I then consider his account of our cognition of our own intellective states. As the discussion in part one make clear, Buridan holds that our concepts of intellect and of intellective states are both derived (inferentially) from subjective “experience” of our own states and rational activities. In part two, therefore, I try to elucidate Buridan’s notion of experience. Ultimately, I argue that it is a non-conceptual, non-discursive mode of self-awareness. I suggest, moreover, that it might best be understood in terms of our own notion of phenomenal consciousness. On the interpretation I advance, then, it turns out that, for Buridan, our concept of the intellect itself and, hence, the science of (human) psychology in general, is ultimately grounded in phenomenal experience of our own intellective states.