Our sharpest break with the tradition has come with the realization of the disunity of knowledge (of thought, the mind, the world, and pretty much else that concerns philosophy). We are no longer trying to construct “a system;” we are not looking for “the foundations” of a single structure; we have abandoned the belief in completeness and in our capacity to make everything cohere.
A vivid expression of this revolt against the entire philosophical tradition from Aristotle to Hegel is due to Nietzsche who declared his “profound aversion to reposing once and for all in any one total view of the world” and proclaimed, instead, the “fascination of the opposing point of view: refusal to be deprived of the stimulus of the enigmatic.” (The Will to Power, 470) The remark provides a key to Nietzsche’s writing and thinking. It helps to make sense of his aphoristic style as well as of his belief in many perspectives. Not that readers of Nietzsche have always appreciated this point. Nietzsche himself wrote in a sketch for his last book: “I mistrust all systems and systematizers; perhaps one [of them] will even discover behind this book the system I have sought to avoid. The will to system is a dishonesty for a philosopher.”
Another expression of this same idea is found in Wittgenstein’s later writings. He asks himself there what reasons he has for trusting text-books of physics and he answers: “I have no grounds for not trusting them. And I trust them. I know how such books are produced – or rather, I believe I know. I have some evidence, but it does not go very far and is of a very scattered kind. I have heard, seen, and read various things.” (On Certainty, 600) This is, of course, not a biographical note but meant to reveal the status of our usual claims to knowledge. What we call knowledge is, indeed, of a scattered kind. Linked to this thought is Wittgenstein’s realization that the mind (or soul or self) is not a unity – a conviction that the tradition has made a supporting pillar for its belief in the immortality of the soul. (A simple substance, it says, cannot disappear through a process of disintegration.)
Michael Foucault speaks of different discourses with their own distinctive internal rules and he points out that not everything possible is actually ever said. “We must look, therefore, for the principle of rarification or at least of non-filling of the field of possible formulations… The discursive formation is not therefore a developing totality, … it is a distribution of gaps, voids, absences, limits, divisions.” (The Archaeology of Knowledge, p. 119) And again, in slightly different language: “The archive cannot be described in its totality… It emerges in fragments, regions, levels…” (p. 130)
While Nietzsche, Wittgenstein, and Foucault agree that there is nothing uniquely foundational for philosophy to think about, they do not mean to say that it doesn’t matter what we make the subject of our thinking. Some philosophical questions are clearly more urgent than others. For us the decisive issue is now our individual, social, and political existence as human beings. The pressing issue is what it means to be human and all three, Nietzsche, Wittgenstein, and Foucault, wrestled with that.