Ignorance: (On the Wider Implications of Deficient Knowledge)

Chapter 2 Questions and Insolubilia

28 Incapacity Regarding Questions It is instructive to take an erotetic—that is, question-oriented—view of knowledge and ignorance. After all, someone knows that p when (and only when) they can cogently give a correct answer to the question “Is p the case?” and an answer is given cogently when (and only when) the giver has a satisfactory rationale for giving it. There are two possibilities for erotetic ignorance: (1) generic question -resolving incapacity (“There is some question Q that one cannot answer”) and (2) concrete question-resolving incapacity (“Q is a specific , here-and-now identifiable question that one cannot answer”).1 Even as there is concrete and indefinite knowledge, so there is concrete and generic ignorance as well. But there is a crucial difference here. For in the case of questions—unlike factual knowledge—we can be concretely specific regarding our incapacity. We cannot coherently say “p is a specific truth (fact) I do not know.” But saying “Q is a specific question I cannot answer” is altogether unproblematic. 2 Questions and Insolubilia rescher ign text.indd 28 12/19/08 9:45:41 AM Questions and Insolubilia 29 When we look at cognition from the angle of questions rather than that of knowledge, ignorance becomes identifiable. Erotetic ignorance —the inability to answer questions—is accordingly something quite different from propositional ignorance: the failure to know truths. For with erotetic ignorance we can hope to get beyond generalities to identify questions that we cannot answer. But this sort of specificity is something that we cannot manage in the realm of propositional knowledge. Kant's Principle New knowledge emerging from the progress of science can bear very differently on the matter of questions. Specifically, in the course of cognitive progress we can discover the following: 1. New (that is, different) answers to old questions. 2. New questions. 3. The inappropriateness or illegitimacy of old questions. With 1 we learn that the wrong answer has been given to an old question: we uncover an error of commission in our previous question -answering endeavors. With 2 we discover that there are certain questions which have not heretofore been posed at all: we uncover an error of omission in our former question-asking endeavors. Finally, with 3 we find that one has asked the wrong question altogether: we uncover an error of commission in our former question-asking endeavors, which are now seen to rest on incorrect presuppositions (and are thus generally bound up with type 1 discoveries). Three rather different sorts of cognitive progress are thus involved here— different from one another and from the traditional view of cognitive progress in terms of a straightforward “accretion of further knowledge.” rescher ign text.indd 29 12/19/08 9:45:41 AM 30 Questions and Insolubilia The coming to be and passing away of questions are phenomena that can be mooted on this basis. A question arises at the time t if it then can meaningfully be posed because all its presuppositions are then taken to be true. And a question dissolves at t if one or another of its previously accepted presuppositions is no longer accepted. Any state of science will remove certain questions from the agenda and dismiss them as inappropriate. Newtonian dynamics dismissed the question, “What cause is operative to keep a body in movement (with a uniform velocity in a straight line) once an impressed force has set it into motion?” Modern quantum theory does not allow us to ask, “What caused this atom on californium to disintegrate after exactly 32.53 days, rather than, say, a day or two later?” Scientific questions should thus be regarded as arising in a historical setting. They arise at some juncture and not at others; they can be born and then die away. A change of mind about the appropriate answer to some question will unravel the entire fabric of questions that presupposed this earlier answer. For if we change our mind regarding the correct answer to one member of a chain of questions, then the whole of a subsequent course of questioning may well collapse. If we abandon the luminiferous ether as a vehicle for electromagnetic radiation, then we lose at one stroke the whole host of questions about its composition, structure, mode of operation, origin, and so on. Epistemic change over time thus relates not only to what is “known” but also to what can be...