Concepts and Philosophical Puzzlement
Michael Dummett has suggested that philosophical puzzlement is caused by our “imperfect mastery” of our concepts (he is by no means the only person to think this way). He gives the example of the concepts past and future: we understand these concepts well enough to make judgments about the past and future of an ordinary kind, but if we ask ourselves why cannot affect the past as we can affect the future we find ourselves puzzled. The reason for this, he says, echoing Wittgenstein, is that we don’t “command a clear view” of the concepts past and future. That is, we have only an “imperfect mastery” of these concepts—a partial mastery, a tenuous grasp, a limited understanding. There is something about them we fail to grasp, and this failure generates perplexity. Such a view contrasts with the idea that we have a limited understanding of the world beyond concepts: we fail to grasp important aspects of reality not our conceptual representation of it; and this is what generates philosophical perplexity. Dummett gives the example of quantum theory: here we have an effective theory for making predictions but we have no satisfactory interpretation of the theory. Some may say this is because we lack knowledge of quantum reality itself; others may say we lack an adequate grasp of the concepts of quantum theory (analytical knowledge not empirical knowledge). Dummett is proposing that philosophical perplexity arises from a deficit in our knowledge of our own concepts not from a deficit in our knowledge of what these concepts are about (sense not reference, in effect).
This thesis raises some interesting questions. Is the thesis true of all concepts or only some? Do we have perfect mastery of some of our concepts, so that no philosophical puzzlement is occasioned by them? Which are they? Are there degrees of imperfection in our mastery of concepts—are some very imperfectly grasped while others are only mildly so? Are there concepts we possess that we have no understanding of—concepts we can’t use at all? If that is impossible, what about concepts that are almost completely opaque to us? How deep can the imperfection in our mastery go? And why should this be so—why should our concepts lack in transparency? After all, they exist in our minds and we use them in our conscious thought, so why should our grasp of them be so imperfect? Why would nature (or God: Dummett was a Catholic) design us this way? Bear in mind that concepts constitute the meaning of words, so that Dummett’s thesis applies to them too—we have imperfect mastery of the meaning of our own words. We lack knowledge of these meanings; we are ignorant of what we mean by our own words. By contrast there is no paradox in the idea that we are ignorant of the world beyond our conceiving minds—time itself in the case Dummett cites. But it is surely strange to think that our own concepts and meanings are routinely closed off from our knowledge of them. If some philosophical problems are insoluble that would imply that we can never gain access to the content of our own concepts; maybe so, but the idea requires careful consideration. It seems to imply the existence of a vast conceptual unconscious—all the stuff that we fail to know consciously when we employ concepts. Why does this unconscious exist? How inaccessible is it? How is it connected to our conscious thought? Our concepts allow us to make intelligent judgments, both practical and theoretical, but they refuse to allow us to make philosophical judgments (or judgments that command general assent). This is curious to say the least.
I don’t say the whole idea is preposterous; indeed I think it raises interesting questions about the nature of conscious thought and the concepts it invokes. But it is not an idea to be thrown out without due consideration. No one would think a comparable thesis holds for the case of other subjects: physics, chemistry, biology, psychology, geography, etc. Here the difficulties stem not from our imperfect mastery of the relevant concepts but from our ignorance of the extra-conceptual world.
 My source for this is a lecture on philosophy of mathematics given by Dummett many years ago (and now available on YouTube).
 Once you make the linguistic turn you are bound to find the difficulty of philosophy to arise from the inscrutability of language, i.e. the elusiveness of our concepts.