in defense of not knowing

IN DEFENSE OF NOT KNOWING

JACK NELSON

QUESTION: What is science? ANSWER: Science, most broadly construed, is the accumula-

tion and systematization of important truths. QUESTION: What is propositional knowledge? ANSWER: Propositional knowledge is an as yet unexplicated

relation between an agent and a true proposition. QUESTION: What has knowledge got to do with science? ANSWER: Very little, if anything.

I take only the last of the above answers to be controversial. I shall argue for the correctness of that answer by arguing that knowledge is, to a far greater extent than most philosophers are willing to admit, a psychological concept. Roughly put, my thesis is that the presence of knowledge requires the absence of doubt. How this psychologized view of knowledge supports the thesis that knowledge has little to do with science will, I hope, become apparent in what follows.

I begin by arguing that no simple justified-true-belief (here- after 'JTB') analysis can provide us with sufficient conditions for knowing, even overlooking the Gettier problem. But my general claim is not that something like a JTB analysis which incorporates my thesis that knowledge is incompatible with doubt is the right analysis of knowledge. Rather, I hope to show that whatever analysis of knowledge is ultimately accepted, whether it be a JTB analysis, a causal analysis, or yet some other kind, that analysis will have to include or entail the requirement that the putative knower not have any doubts about what he is alleged to know. I will, that is to say, be arguing for a necessary, not for a sufficient, condition for knowing.

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I

Suppose a fair coin is about to be flipped. Here I cannot truly say 'I know it will come up heads,' even if I believe it will, and it does. I have no epistemological right to believe it will come up heads; my belief is epistemologically unjustified. Consider next an urn containing 100 marbles, 99 of which are red and one of which is white. Suppose I know that such are the contents of the urn and am about to draw, while blindfolded, a marble from the urn. Here I surely am licensed in predicting that the marble I draw will be red. Presumably I also believe it will be red. But it seems perfectly clear that I do not know it will be red. Being aware of the contents of the urn, and being a rational man, I realize I might, just might, draw the white marble. But suppose luck is not against me and I do draw a red marble. It follows that I had a justified, true belief which did not constitute knowledge. So much the worse, it would seem, for all standard JTB analyses of knowledge.

But perhaps the above case, and cases like it, only seem to be counterexamples to JTB analyses of knowledge. Defenders of such analyses have several lines of defense open to them. They may argue either that, contrary to my claim, I do know I will draw a red marble in the urn case, or that my belief that I will draw a red marble is not epistemologically justified.

A proponent of the first of the above lines of defense might simply insist that my intuitions are wrong, that in the marble case and cases like it one can and very often does know what the results will be. If this is his only defense we are near an impasse, one intuition against another. I can only repeat that my intuition is very strong, and cite some supporting intutions. If I do know I will draw a red marble, then surely I should also know I will not draw the one white marble. But it seems very clear that normally do not know this. It is just very unlikely that I will draw the white marble, and my knowing this seems to keep me from knowing I will not draw the lone white marble.

Consider the second possible defense outlined above: that in the drawing case I am not justified in believing I will draw a red marble (and hence that we do not have an instance o f a justified true belief which is not knowledge). One might argue that I am not justified in believing I will draw a red marble because my evidence is not strong enough, my evidence makes it only .99 probable that I will draw a red marble. Alternatively, one might argue that statistical or probabilistic evidence is never enough to

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make a belief justified, in the sense required for knowledge. Neither of the above lines of reasoning seems very promising.

If a probability of .99 does not justify my believing that I will draw a red marble, then surely a probability of .999 should. And an arbitrarily high probability, so long as it remains less than 1.0, can be obtained in the urn case by ~c'reasing the number of red marbles. Yet as long as there is one white marble in the urn, and I am aware of this, I am normally inclined to say I do not know the marble I draw will be red. For I do not know I will not draw the one white marble. It becomes increasingly unlikely that I will do so, but the unlikely does sometimes happen.

There remains the suggestion that probabilistic and statistical evidence is never sufficient to make a belief epistemologically justified. In the urn case, it might be argued, the problem is that it is always just a matter of chance whether the one white marble is or is not drawn. Given a long enough series of draws, the white marble will be drawn sooner or later; which draw it is drawn on is just a matter of chance. 1 Any of the draws could equally well produce it. Generally, the problem with statistical and probabilistic evidence is that the unlikely's not occurring is always, at least relative to the evidence available, just a matter of chance. And this element of chance or luck is, or so it might be argued, incompatible with knowledge. Thus, it might be concluded, the only way to secure an adequate account of knowledge is to explicate 'justified belief' so as to require something stronger than statistical or probabilistic evidence. This approach does explain why I do not know I will draw a red marble. But it also seems to place virtually all empirical propositions beyond our ken, for it seems reasonable to think that in the end virtually all evidence for empirical propositions reduces to statistical or probabilistic evidence.

For example, when in a major city such as Philadelphia, I am normally prepared to claim I know where my car is parked. Yet most major cities, including Philadelphia, have high auto theft rates. In fact the rate is almost certainly at such a level that it is more likely that my car has been stolen than it is that my lottery ticket is the winning ticket in the Pennsylvania state lottery. If the probabilistic nature of the evidence keeps me from knowing I will draw a red marble in the urn case, then the probabilistic nature of the evidence concerning the possible theft of my car should also keep me from knowing where that vehicle is parked. I f I do not know that my car has not been stolen, I cannot, it would seem, know where it is parked. Yet I normally do know where it is parked.

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II

At least two avenues of exploration now suggest themselves. We might look to the structure of epistemic justification, hoping that though in virtually all cases of reasonable belief our evidence is probabilistic in nature, there is nonetheless something distinctive about the structure of our reasoning in cases where our beliefs constitute knowledge. Alternatively we might look to the attitude of the believer towards his evidence and the believed proposition, hoping there is something distinctive about this attitude in cases of knowledge. Recent philosophical literature contains at least two noteworthy attempts to specify what is distinctive about epistemic justification vis-a-vis mere high probability. These are the ap- proaches of Gilbert Harman and James Cargile. 2

Harman's intutions about straight probability cases are the same as those expressed in Section I of this paper. His example is that of someone who has purchased a ticket in a lottery. "In the lottery case a person cannot know he will lose no matter how probable this is." (APQ, p . 166.) Yet, Harman holds, in more normal cases, e.g., the case of a witness testifying that p, one can come to know p though "the likelihood that a person will lose the lottery is higher than the likelihood that the witness has told the truth..." (APQ, p. 166.) What distinguishes the cases, in Harman's view, is not the likelihood of being right or wrong, but the structure of the reasoning used in reaching the believed proposition.

For Harman, inductive reasoning always has, an an end result, a statement of the form 'X because Y'. Furthermore, to be successful or acceptable Y must be the best of competing explanations of X. Every knowledge claim must, accordingly, be either of the form 'X because Y' or be obtained by deductive reasoning (from 'X because Y' one can deduce both X and Y). According to Harman the claim 'I will lose the lottery' cannot be reached either by inductive reasoning (construed as above) or by deductive reasoning. Deduction will, in this case, yield only a probability statement concerning the outcome of the lottery. Inductive reasoning is not applicable because here there is no explanation (and hence no best explanation) of why my ticket will not be the winning ticket. 3

Harman's principle P places a further restriction on what is to count as knowledge:

Reasoning that essentially involves false conclusions, inter- mediate or final, cannot give one knowledge. (Thought, p. 47.)

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Each of the foregoing conditions is a necessary condit ion for knowledge. They are not, in Harman's view, joint ly sufficient. A requirement barring the presence o f evidence which undermines the purported knowledge claim but is not possessed by the purported knower must also be added. 4

Harman tries to use his thesis that induction should be construed as inference to the best explanation to explain why, though high probabil i ty by itself does not license knowledge claims, knowledge based on probabilistic or statistical evidence is still possible. One of Harman's own examples will be helpful here.

Suppose that John and Sam have tossed a fair coin to determine who will have a new hundred-dollar bill. The new hundreds are easily recognizable, being pink, an in- novation of the Treasury Department. An hour later, Peter, who knows about the toss, sees John with a new hundred-dollar bill. Pe te r realizes that John could have received such a bill in only two ways, the most likely being that he won the toss with Sam. There is also an extremely unlikely way, hardly even worth considering. That morning, as a result of a Consumer Digest promotion scheme, some person, chosen at random from the population of the United States, has received the only other pink hundred now in circulation. The odds are two-hundred million to one that John did not receive the Digest's bill. So Peter infers that John won the toss with Sam. He infers that the explanation of John's having the bill is that he won the toss and not that he received the Digest's bill. If the explanation is right, an ordinary natu- ral judgment about the coin toss case would be that Peter knows John won the toss. (APQ, p. 168.)

' John has a pink hundred dollar bill because he won the coin toss with Sam' is the explanation which Peter infers. From it he deduces, and thus comes to know, ' John won the coin toss with Sam'. The explanation is a best explanation because it makes John's having a pink hundred-dollar bill much more probable than does the alternative explanation that John won the Consumer Digest lot tery.

Harman's joint advocacy of principle P and the thesis that all (acceptable) inductive inferences are inferences to the best explanation at least appears to enjoy several very considerable advantages. First, it does explain or purport to explain how we can know a great many things even though in almost all cases the chances of our being right are at best very high. And it does this without making high probabil i ty (plus truth and belief) alone sufficient for

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knowledge. Secondly, it purports to solve the Gettier problem. Just how Harman thinks his position solves the Gettier prob-

lem is not entirely clear. At times his claim seems to be that every Gettier case will turn out to involve inductive reasoning (an inference to the best explanation), either conscious or unconscious, which makes essential use of at least one false proposition, and will thus be blocked by principle P. (See Thought, p. 141.) But here one might well object that people do not always proceed correctly, i.e., via inferences to the best explanation, in their conscious reasoning. This being so, the objection continues, there is little reason to think they always so proceed in their unconscious reasoning. If we sometimes do reason badly unconsciously (e.g., move from 'very probably p ' to p) there may well be Gettier cases which involve neither conscious nor unconscious reasoning which makes essential use of a false proposition. To this Harman must either reply that, deductive reasoning apart, all unconscious reasoning does proceed via inferences to the best explanation, or that non-deductive reasoning which does not so proceed may occur but cannot yield knowledge.

The first of the above responses is implausible; it amounts to no more than a refusal to countenance the objection in question. The second is more promising, and is presumably the one Harman would give. But now Harman's theory begins to appear in a new light. Gettier cases are, to be sure, blocked. But if we do not always reason unconsciously via inferences to the best explanation the possibility arises that some or many of the cases in which we do not do so are non-Gettier cases, i.e., cases which seem to be straightforward instances of knowledge. Harman's theory must apparently dictate that it will turn out that this is not so, that our unconscious reasoning is correct in all or almost all cases which we are now prepared to call cases of knowledge. So Harman's theory turns out to have very considerable empirical content. This being so, acceptance of that theory must wait on our finding a criterion for distinguishing kinds of unconscious reasoning (for telling when we do and when we do not reason via inferences to the best explanation), and on the results of our applying that criterion to a wide range of Gettier and non-Gettier cases. What such a criterion might be like is not at all apparent.

It is also not entirely clear that Harman's principle P is an innocuous principle. Is it really the case that no false belief can be essential to reasoning which culminates in knowledge? Consider the high school science teacher who has never heard of Einsteinean relativity theory. He uses Newton's Laws to predict how certain

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bodies will behave. They do so behave. It certainly seems that he knows they will so behave. But Newton's Laws, at least in the unrestricted form in which our hypothetical teacher believes them, are false. It may be that had our teacher believed only the restricted form of these laws which are compatible with relativity theory he could still have made the predictions in question. But he does not in fact believe the restricted versions. A similar case is that of a Ptolemaic astronomer who uses his false theory of epicycles to predict where Venus will appear in the sky on a particular night. His prediction is correct; he knows, most would agree, where Venus will appear. Yet involved in his reasoning are many beliefs about the motion of the planets through the sky. It might be replied that the false parts of his theory are not essential to his reasoning. Someone who treated the Ptolemaic system only as a way of predicting the positions of heavenly bodies in the night sky, and not as an accurate description of the actual paths of the planets, could have made the same prediction. This is true, but those beliefs are not beliefs of our Ptolemaic astronomer, s

Even if the aforementioned difficulties are overcome there remains a very serious objection to Harman's position. This can be brought out by looking more closely at the pink hundred dollar bill case. Here Peter sees John with a pink hundred, makes an inference to the best explanation, and comes to know that John won the bill in the coin toss with Sam. If Peter has his wits about him he should now also come to know that Sam did not acquire the bill in question in the Consumer Digest lottery. One and the same bill cannot have been won in both ways. But can Peter come to know this? Remember that Harman holds that "In the lottery case a person cannot know he will lose no matter how probable this is." (APQ, p. 166.) Now if there were no coin toss between Sam and John, or if Peter did not see John with a pink hundred, Peter would not be licensed in making any inference concerning the outcome of the Consumer Digest promotion. How, when the coin toss and the promotion are independent events, does Peter's seeing John with a pink hundred license the conclusion that that hundred was not won in the promotion? Note that John's having a pink hundred actually increases the odds that John has won the Consumer Digest lottery. It increases the odds because Peter can now rule out the possibility that John lost both the coin toss and the lottery. 6 And how an event's becoming more probable can produce the knowledge that the event did not occur is hard to understand.

Harman's response will presumably be that the inference to

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the best explanation - that John won the bill in question in the coin toss - is so powerful that it allows us to disregard the increased odds of John's having won the bill in the lottery. Harman does discuss related cases. He notes that we might, on the basis of various evidence, conclude that the butler is the murderer and go on to conclude that the butler did not win the lottery which he had entered. We cannot know directly that the butler lost the lottery. But because his having won it does not fit well with the view that he is the murderer, we can know indirectly that he lost. Such is the power of what Harman calls "total views". Similarly, though we cannot come to know directly that Jones will lose the lottery in which he is entered (by considering the high odds against his winning) we can come to know this indirectly. For we might "infer and come to know that we will be seeing Jones for lunch tomorrow" (he said he would meet us for lunch) and we might know that his seeing us for lunch is incompatible with his winning the lottery ("if he won the lottery he would have to be in Trenton tomorrow to receive his prize and would not be able to meet us for lunch.") (Thought, p. 161.)

But these cases are unconvincing. About the butler case Har- man suggests that we should be licensed in reasoning as follows: 'The butler seems to have done it. He seems to have ample motive (and this, in part, is what makes the conclusion that he did it the best of competing explanations). But if he did win the lottery we are wrong about his having a motive, so he must not have won the lottery. ' But this just won' t do. Surely in so far as the butler's having won the lottery weakens our case against him, and we agree that we cannot be sure that he lost the lottery, we have to grant that our case against him is weakened. Insofar as we grant we cannot be sure Jones lost the lottery and his winning it is incompatible with his meeting us for lunch, we cannot be sure he will meet us for lunch. It might, of course, still be reasonable to believe Jones will meet us for lunch, and that the butler did iti but this argues for our separating true reasonable beliefs (even those based on inferences to the best explanationJ from knowledge, not for our being able to come to know in Harman's round-about way, that the butler and Jones lost the lotteries in which they were entered.

I conclude that as interesting and useful as Harman's notion of inference to the best explanation may be, it does not supply us with an account of knowledge which adequately explains our intutions about cases where we have at best high probability.

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III

James Cargile has suggested a quite different way of avoiding both the Gettier problem and the counter-intuitive view that high probabil i ty alone is enough to make a belief justified in the sense required for knowledge.

Cargile develops his position by objecting to the frequently defended view that the only thing which need distinguish a case of knowledge from a case of not knowing is the t ru th of the belief in question. Evidence which c a n lead one to a false belief cannot provide one with knowledge, or so CarNie holds. Two of the examples CarNie offers in support of his posit ion involve Jones. In the first Jones appears in the guise of a street corner girl watcher:

Five people pass and [Jones] forms the five firm con- victions ' there goes a woman - there goes a woman - and there goes another - and another - and another ' . Actually, it is a group from a nearby convention of female impersonators. But the third member of the group is the group's secretary, a female. (P. 149.)

In the second example Jones is port rayed as having a tedious job which requires

him to sit by a conveyor belt carrying boxes of water- melons and to mark on the side of each box whether it contains 5, 6, or 7 melons and then close it. He marks a thousand boxes a day and makes a mistake about once a week. (P. 151.)

CarNie takes it as obvious that in the girl watcher case Jones does not know that the third person he sees is a woman. His evidence, though very good, is not good enough to prevent error. The very same kind of evidence (the visual appearance of the person) does lead him to error in the other four cases. In the second example Jones' evidence is also not good enough to prevent error - he does make a mistake in counting about once a week. Thus, in Cargile's view, Jones does not normally know how many melons are in a box when he seals that box and writes either a '5 ' , a '6 ' or a '7 ' on the side. He does not know because his normal counting procedure is fallible. In any given case the warrant he has for believing that there are so-and-so many melons in the crate he has just sealed is no better than the warrant he had last time he miscounted.

Cargile's own thesis is that for a belief to be justified in the sense required for knowledge it must rest on evidence or other warrants which are strong enough, in the given situation, to _guaran-

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tee the truth of that belief. Perhaps because he sees the difficulties involved in explicitly stating his view Cargile himself opts for the following circular account of an epistemically justified belief: "a belief based on reasons (or other warrants) which are good enough, for the given situation, that ... it qualifies as knowledge." (Pp. 146-47.) (All justified beliefs are, thus true.) It is not the avowed circularity of Cargile's position to which I wish to object, 7 but rather the suggestion that there is a notion of justification which is weaker than entailment but stronger than that provided by mere high probability.

Consider the reasons Cargile gives for using the phrase "for the given situation" rather than "for any situation" in his circular account. His claim is that the latter reading leads to the "pro- foundly skeptical" consequence that "if a certain kind of evidence ever proved inadequate to protect you from error, then it never could in any situation be good enough to qualify you as knowing." (P. 150.) And this is not in fact the way we do treat evidence. In Cargile's girl watcher case the visual appearance of the figure passing before Jones is not enough to prevent error, and thus not enough to give him knowledge that the third figure is a girl. But in a more normal situation, where there are no female impersonators about, the visual appearance of a person is enough to give one knowledge of the sex of that person. So whether evidence is good enough to make a belief knowledge does, Cargile holds, depend on the particular context or situation in question. The alternative, making a particular kind of evidence either always good enough to yield knowledge or never good enough to do so, leads to skepticism because there is no or almost no evidence which is always good enough to prevent error. The obvious female appearance of a person is not, for example, good enough evidence to prevent error in all situations.

Skepticism is, to be sure, threatening here. But Cargile's way of escaping that skepticism is unsatisfactory. At least it is unsatisfactory if one accepts the intuition that knowing p is incompatible with its being to any degree a matter of luck or chance that one is right about p. (And this intuition does seem to lie behind Cargile's insistence that to have knowledge one's evidence must be good enough to guarantee truth.) Consider the girl watcher case once more.

Jones is pursuing his favorite lunchtime occupation in a city in which there does happen to be a female impersonators' convention. Smith is doing the same in a city in which there is no such convention. Each sees a girl pass and forms the firm conviction

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'There goes a beautiful girl'. On Cargile's analysis Smith knows that the figure which has just passed him is a girl, but Jones does not know the figure which has just passed him is a girl, though it is, and his belief that it is a fully reasonable belief. Jones does not have knowledge because, though he is right, he might not have been; in his city the kind of evidence he does have can, at present, lead to a false belief, though it did not do so in this case. This seems very reasonable. But viewed in another way, it is just pure luck that Smith has knowledge and Jones does not, for it is just luck or chance that Jones is pursuing his favorite noontime avoca- tion in a city where there is a female impersonators' convention, whereas Smith is not. Each possesses evidence of exactly the same sort for his belief. Their positions could just as well have been reversed; the impersonators' convention could just as well have been in Smith's city rather than in Jones' city. It is just bad luck, the presence of an unusual convention, that prohibits Jones from knowing the figure passing him is a girl. On the other hand, it is just the unlikely's not happening that allows Smith to know, it is just Smith's good luck that there is no female impersonators' convention in his city.

If the element of luck or chance is incompatible with knowledge, then Smith and Jones should be (but are not, on Cargile's analysis) equally debarred from knowledge. Both their beliefs are correct, both are based on good evidence, and it is just a matter of chance that that evidence will prevent errors in Smith's city but may not do so in Jones' city.

If the foregoing were the only problem with making the evaluation of evidence context relative we might simply swallow that oddity and note that the price of avoiding skepticism is the admission of a kind of second order skepticism. That is, on an account like Cargile's there will, hopefully, very often be situations or contexts in which our evidence is good enough to prevent error. In these situations we will have knowledge. However, whether or not we are, in a particular case, in such a situation is a matter not so often within our ken. In the above case, for example, it is most likely that Smith does not know there is no female impersonators' convention in his city. Most likely he neither believes nor dis- believes that there is such a convention in his city. What is important for knowledge, on Cargile's view, is that there be no such convention, not that Smith know or believe there is no such convention in his city. But it follows that Smith does not know he knows the figure which passes him is a girl, for he does not know his evidence is good enough to prevent error. Similarly, in most

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everyday instances of knowledge, we may know, on Cargile's account, but we will not know that we know.

But there are major objections other than just accepting second-order skepticism to the thesis that the evaluation of evidence is always context relative. The most major of these is in finding some criterion for determining the context against which our evidence is to be evaluated in any particular instance. In the above case w e stipulated that there is a female impersonators' convention in Jones' city. But perhaps Jones is carrying on his girl watching on the north side, and the convention is on the south side, and no conventioneers have strayed to the north side. In this situation Jones' perceptual evidence begins to look good enough to prevent error. For in this situation there are no female impersonators on the north side. Just how far must Jones be from a female impersonator before he is in a situation where his evidence will prevent error? No non-arbitrary answer seems possible.

What does seem possible is to relativise knowledge. We might say that every knowledge ascription really has the following form "A knows p relative to context C." There would then be no answer to the question 'Does A know p? ' - just as there is no answer to 'Is Fido big?' The proper responses would be 'Is Fido a big what?' Does A know p relative to what context? Relative to some contexts A might well know p, relative to other, wider contexts, he will not, But this seems an unattractive view. I do know where my car is parked, simpliciter. Moreover, if knowledge is thus relativised this is surely more evidence that there is a wide schism between science and knowledge.

Finally, it is not clear that the examples Cargile gives o f situations where the evidence available is good enough to prevent error really are examples of such situations. In the melon counter case Cargile stresses that even though the counter (Jones again) normally does not know how many melons are in a box he has just sealed, "it would be very easy for Jones to make absolutely certain that there was no probability whatsoever of his being wrong about the box in question. He could open it and do a careful recount. I do not hold with the view according to which zero probability applies only to what is logically impossible." (P. 151.) I, on the other hand, simply do not see how counting a second time, however carefully, will yield evidence different in kind from the evidence the counter has after the first count. The first Count is careful - he makes mistakes only once a week (Cargile tells us), or about once in every 5,000 boxes. Does he ever make mistakes on recounts? Most likely he has never done a

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recount - the need has never arisen, But even if he has, surely he has done too few to allow us to ascertain the probability of his making a mistake on a recount. Cargile's point is apparently that the simple fact that in recounts Jones does or would count very carefully is enough to guarantee that he will never make a mistake in so counting. But this is unconvincing. All manner of things could happen. Some synapse in Jones' brain could misfire, yielding the wrong count even on the most careful procedure. All either the counter or the observers are licensed in concluding is that a mistake on a recount is extremely unlikely. But if this is all, then on Cargile's account the melon counter cannot come to know how many melons are in a crate by doing a recount.

1V

I turn now to a defense of an avowedly psychologized view of knowledge. The thesis I wish to defend is that knowledge pre- cludes doubt. More formally, I shall defend the following thesis:

I: 'A knows p' entails 'A has no conscious doubts about p. '

Note, again, that it is a necessary, not a sufficient, condition for knowing that I am defending. There are, of course, other ways to psychologize knowledge. One might propose that what is required is that the knower be certain of the proposition that he allegedly knows, or that he not view his evidence or other warrants for that proposition as being, in the end, probabilistic in nature, or that he be of such a frame of mind that the supposition that the allegedly known proposition is false created in him a demand for an explanation of why it is false. All of these proposed necessary conditions for knowledge will converge in ruling out obvious probabilistic cases, e.g., lotteries, as cases where knowledge of the outcome is possible. Even if one believes one's lottery ticket will lose, one normally has some doubt about this (otherwise one would not have bought the ticket), one is not certain that it will lose, one sees the evidence for the belief that it will lose as dearly probabilistic in nature, and one will not be inclined to ask why it does not lose if it does not. (In a lottery some ticket has to win, that it turns out to be my ticket normally needs no special explanation. But if one's car is not where one remembers parking it, that does require some special explanation. Was it stolen? Did the police tow it away? Did I lend it to a friend?)

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The reasons for not making certainty a requirement for knowledge are well known. Jones walks into a room for the first time and sees, and thus comes to know, that there is a telephone on the desk. But in this and the vast majority of normal cases it would be a mistake to say that Jones is either certain or uncertain of the truth of the proposition he thus comes to believe. Certainty is not here in question. Jones simply sees and takes the telephone to be what it is. The thought that what he sees might not be a telephone but, say, a stage prop never occurs to him. I suggest that the vast majority o f cases in which we are prepared to ascribe knowledge are cases like the above, where there is no reflection, no consideration of evidence, and neither certainty nor uncertain- ty. Thus to make psychological certainty a necessary condition for knowledge would do very considerable violence to our pre-analytic intuitions about knowing. There is nothing sacrosanct about pre- analytic intuitions. But neither is there virtue in needlessly over- turning them.

As Harman has shown, there are cases where the evidence one has is, and is perceived as being, clearly probabilistic in nature but which also appear to yield knowledge. One is his example o f the pink hundred dollar bill. Here Harman thinks everyone will agree that upon seeing John with a pink hundred one can come to know he won it in the coin toss with Sam. A more convincing case may be taking samples from two batches of widgets, where one knows that one of the batches is largely defective, containing 70% defective widgets. The non-defective batch contains only 1% defective widgets. If one randomly selects ten widgets from one batch and discovers that seven of them are defective, one can thereby come to know that that batch is the generally defective batch, Harman argues. It is, of course, possible that the sampled batch is the non-defective one and we were just very unlucky in drawing our samples. But that this is possible does not prevent one from knowing the sampled batch is the defective one, assuming it is. (APQ, p. 170.)

One's intuitions about cases such as those Harman cites tend to become obscured with reflection. I can report o f myself that on first encountering these cases I thought Harman's intuitions correct. If they are, then merely realizing that one's evidence is probabilistic in nature does not prevent one from knowing. I am no longer sure about Harman's cases, but suggest that there are more convincing cases. Consider what would happen if one tried to convince a friend that he might now be dreaming, or that what seems to be his hand before his face might be an illusion. One

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points out, in the latter case, that illusions do occur, that it-is possible that the coffee he just drank was drugged, that hypnotism is not an impossible explanation for why he seems to see a hand before him. It is my own experience that the most one can get people to grant is that it is just possible that they are now experiencing an illusion or delusion. Some will not admit even this much about cases of present sensation but will about other matters which we would pre-analytically judge nearly as certain (what day it is, where one's car is parked). But even when one admits that the evidence available, or perceptual warrants, does (do) not make the allegedly known proposition ('This is a hand before me' , 'Today is Tuesday') certain, one usually still claims to know that that proposition is true. Sometimes being confronted with the fact that our evidence is in the end probabilistic or statistical just does not shake our faith in the proposition in question. If we adopt the view that it is the presence of conscious doubt which is incompatible with knowledge, and not the thesis that it is realizing one's evidence is probabilistic or statistical in nature which debars one from knowing, we will be able to grant that we do normally know in the sorts of cases just described.

Other cases can also be more naturally accounted for by adopting the conscious doubt thesis. Cargile does not tell us whether his melon counter is aware of how often he makes mistakes. Suppose he is not. Then he will surely claim to know how many melons are in the crate he has just sealed. And it seems to me, contra Cargile, that he does know (assuming this is not a case in which he has made a mistake). Now suppose we inform him of his history of mistakes (once every 5000 crates). If we ask him about the crate he has just sealed I suspect he will still claim to know that it contains, e,g., seven melons. But if we point to the stack of several hundred crates he has sealed and marked this day, and ask of one chosen at random whether he knows there are the indicated number of melons in that crate, he may well hesi- tate. It is hard for him to doubt that the crate he just this moment sealed contains seven melons - he just counted them. But it is easier for him to doubt that that crate, one he sealed several hours ago, contains the number o f melons indicated on its fide. After all, he now knows he does sometimes make mistakes, and it is possible that he made a mistake in that case. The difference here seems to be that doubt finds a more ready haven in matters more removed from present sensation and very recent memory. It is just a psychological fact about humans that they cannot easily doubt matters present to their senses, or recently so present. And

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making the absence o f conscious doubt a necessary condition for knowledge rather than the failure to perceive that one's evidence is, in the end, probabilistic or statistical in nature, fits with this fact and my intuitions (at least) about what cases we would countenance as cases of knowledge. This view also explains why Cargile's melon counter is able to come to know how many melons are in a crate sealed some time ago by doing a recount. He need not even count more carefully than before. Simply re- counting will, we can reasonably expect, remove any doubt he might have about the number o f melons in that crate.

The absence of conscious doubt requirement also helps explain, it seems to me, the slipperiness o f one's intuitions about Harman's cases. In the pink hundred dollar bill case one first has no doubts (and thus knows) that John got Iris pink hundred in the coin toss with Sam. But when queried, or when one reflects, one realizes it is possible he got it in some other way, e.g., the Consumer's Digest lottery. The more these possibilities work on one the more likely it is one will come to have some conscious doubt about how John got his new pink hundred. And when one comes to doubt, one ceases to know. So too in the widget sampling case.

The reasons detailed above for preferring the absence of con- scions doubt requirement to the requirement that one not see one's evidence as probabilistic in nature also seem to be reasons for preferring the doubt requirement to the requirement that one be of a frame of mind so as to be disposed to ask for an explanation if the proposition one allegedly knows tums out to be false.

Cargile's girl watcher case is harder to deal with, as are all such cases which hinge on what Harman has called "evidence one does not possess". The position I am forced to take is that Jones does know, contra Cargile, that the third figure in the group he observes is a woman. He knows this until he is told that most o f the figures in the group were female impersonators, or that there is a female impersonators' convention in town, or until his doubts are roused in some other way. The same line is necessary in Harman's eases. In one o f these "Tom enters a room in which many people are talking excitedly though he cannot understand what they are saying. He sees a copy o f the morning paper on a table. The headline and main story reveal that a famous civil-rights leader has been assassinated." (A/Q, p. 172.) Tom reads the story, it is true, and he believes it. Harman suggests that nonetheless Tom does not come to know of the assassination, for later edi-

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tions of the paper, editions everyone else has read, erroneously report that the leader is still alive. I want to say rather that Tom does know of the assassination, until he is told of the contra- dictory story in later editions, that is, until he comes to have some conscious doubt about the truth of the first story.

The thesis I am defending is that conscious doubt and knowledge are incompatible. Yet most of this paper has been spent discussing the probabilistic nature of evidence in most cases and how this is incompatible with knowledge. The explanation I offer is this: it is simply a psychological matter of fact that most of the time when we realize the evidence or other warrants we have for a proposition make that proposition at most highly probable we also have some conscious doubt about the truth o f that proposition. There are some exceptions to this - cases of present perception and short term memory, most notably. Also, when the odds o f some event's happening become exceedingly small it may be that conscious doubt fails to gain a foothold. Most will agree that if the odds of drawing a white marble from an urn are 1 in 100, one cannot know one will not draw a white marble. But our intuitions become less secure if we dramatically reduce the odds. What if there are a million marbles in the urn, and only one white? Can one then know one will not draw the white marble? The answer depends, I suggest, on whether or not one does have any conscious doubt about the outcome of the proposed draw. Some will have doubts, others not. Some will know the outcome, others will have reasonable beliefs but not know.

V

In the Meno Socrates compares beliefs with statues of Daeda- lus, which were supposed to run away and escape if not tied down, but which were very valuable if securely tethered. "Once they [beliefs] are tied down, they become knowledge, and are stable. That is why knowledge is something more valuable than right opinion. What distinguishes one from the other is the teth- er." [97d-98a]. Indeed, it has been a common view ever since, and perhaps from before, Socrates' time that knowledge is more solid and stable than is true belief which is not knowledge, and that knowledge is thus the building blocks out of which science is constructed: In this spirit Quine and Ullian have also praised

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knowledge and the search for knowledge: "Knowledge soberly so-called, on the other hand, is belief at its soberist, farthest from speculation. Knowledge is a laudable aspiration. ' '8 But if my view is correct, knowledge is not at all like this. Indeed it will be justified belief which is not knowledge which is firm and stable, and which constitutes the building blocks of science.

Knowledge will not, if I am right, have the stability Socrates ascribes to it because it will involve a psychological state, the absence of doubt. And people's psychological states or attitudes are notoriously changeable. Normally, on my view, the melon counter of Cargile's example or the lunchtime girl watcher will know, respectively, how many melons are in the crate he has just sealed and the sex of the figure who has just passed. But fairly often the skeptic will be able to destroy their knowledge. The skeptic can point out that the melon counter does make mistakes every so often, and that he has no reason, other than a general probabilistic one, for thinking the present case is not one of these times. II" he thereby induces some doubt in the melon counter concerning the number of melons in the crate in question the melon counter will cease to know how many melons are in that crate. But if later in the day the melon counter comes across the crate in question, with his '7' on the side, and if he is not bearing in mind the skeptic's objections, he may again know there are seven melons in that crate, for he may well not then have any doubts about there being seven melons in the crate. So too with the girl watcher. Even if there is no female impersonators' convention in the girl watcher's city the skeptic can point out that there are such things as female impersonators' conventions, that they have to be held somewhere, and that the girl watcher does not know there is not now such a convention in his city. Furthermore, the skeptic might continue, female impersonators have to be somewhere when not attending conventions; how does the girl watcher know the last figure to pass was not a female impersonator? Such questions may get the girl watcher to admit that the way the passing figures look make his hypotheses about their sex at most probable, not certain; may induce some doubt in him concerning, e.g., the sex of the last figure to pass. But things being as they are the girl watcher will soon forget the skeptic's challenges and return to unreflectively making inward pronouncements about the sex of the passing figures. Doubt will disappear from his mind. Doubt of the sort here in question tends, I suggest, to vanish when one ceases to concentrate on the reasons for it. And knowledge will go and come as the doubt comes and goes. This changeable nature of

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one's knowledge suggests it would be wise to trade in Thesis I for the more carefully worded II.

II: 'A knows that p at time t ' entails 'A does not have any conscious doubt about p at time t'.

Inducing doubt may deprive a person of knowledge, but it need not make his beliefs less justified. Indeed, if the doubt is induced by getting the person in question to see the nature of his evidence in a more complete and realistic way, then his belief will, in one sense, become more reasonable, and perhaps more justified. Surely it is better to hold a reflectively arrived at belief, in full awareness of the probabilistic nature of one's evidence for that belief, even if that belief is not knowledge, than it is to hold an unreflectively arrived at belief which constitutes knowledge only because one is not paying attention to, or aware of, the probabilistic nature of one's evidence for that belief. At least from the vantage point of science, most broadly construed (science as the accumulation and systematization of significant truths) it is better to have critically arrived at and evaluated beliefs, even at the expense of knowledge.

Though the thesis I am defending is at odds with the view of knowledge propounded in the end of the Meno it is not at odds with Socrates' repeated presentation of himself as a man who "knows" only that he knows nothing. Socrates has come to appreciate the fallibility of the human mind and the difficulties inherent in seeking truth. In becoming wise he has become ignor- ant, that is, he has ceased to know. We too should aspire to wisdom rather than to knowledge, where wisdom is having justified beliefs in full awareness of the nature of one's evidence and the possibility that one may be wrong.

It can, of course, be argued that in another way knowledge is preferable to justified belief which is true but not knowledge. In particular, in the practical, everyday affairs of life it would be inconvenient to be required to constantly bear in mind the probabilistic nature of one's evidence, the countless ways in which one's beliefs might (though are unlikely to) go wrong. Here we can almost hear Hume saying, 'scientists and even skeptics become much less reflective and less demanding with regard to evidence when dealing with the mundane matters of everyday life. In doing so they cease to have doubts and attain knowledge.'

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Appendix

There are many as yet unmet objections to the thesis I have been defending. In the brief space that remains I want to com- ment on two of the most major of these. The first is that doubt is an extremely hazy notion, a notion as much in need of elucidation as is that of knowledge. For example, we need to distinguish episodic from dispositional doubt, and each from related but dis- tinct mental states (e.g., from hesitant belief and reluctant assent). I agree that doubt is an unclear notion and that much work needs to be done. But we ought to resist the view that no progress can be made by explicating one unclear concept in terms of another. Indeed, one way to clarify unclear concepts is to show how they are related to one another. (In so far as doubts can be classified as either episodic or dispositional it is episodic doubts that I have been discussing in this paper.) Furthermore, the thrust of this paper has been that knowledge has very little to do with science (science construed as the accumulation and systematization of important truths). In so far as this is true and it is science that we are interested in, it ~s perhaps of no great import that knowledge is no dearer a notion than is doubt.

The second objection I want to try to forestall is that I have paid too much attention to first person claims to know, and have (largely) ignored second and third person ascriptions of knowledge. While it may be that when an agent has doubts about some propositions, p, he will not claim to know p, this does not show that he does not know p. Others may very well say (truly) of this agent that he knows p.

The cases of the hesitant examinee, the philosophical skeptic, and the pathological door checker are often cited in support of the above objection. The examinee case is that of a student in an oral examination who is asked, say, to state Newton's Laws of Motion. He finally does so, perhaps after several false starts, with great hesitancy and unsureness. The examiners will, we are told, decide that the examinee does know the answer to the posed question, even though he is unsure of his answer and might well, in a candid moment, deny that he knows his answer is the right answer.

The first point to note here is that the examiners decide (not discover or ascertain) that the examinee knows the answer (or that he has adequately answered the posed question). This suggests that the case is analogous to that in which one decides to believe the story a student gives in explanation of an unexcused absence from

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an examination. One cannot, in any normal sense, decide to believe something. Rather 'I 've decided to believe you' is an idiom which should usually be parsed as 'I 've decided to act as if I believe y o u . . . ' So too, I suggest, what the examiners do is to decide to act as if the examinee knows the answer to the cited question.

The philosophical skeptic is that ~moying creature who de- nies knowing even the most obvious of things, e.g., that 2+2=4 and that he is sitting by a roaring fire (when he is). But, it is purported, we have no qualms about saying of him that he does know these things; he just doesn't know that he knows them. Most skeptics, at least those such as Descartes and Hume, do not practice skepticism as a way of life. In everyday matters they act and talk like ordinary men. During such periods they presumably know and even claim to know vast numbers of things. What is at issue is whether or not they have propositional knowledge even during their most skeptical moments. Is the problem just that they have yastly too high standards of knowledge and thus know but do not realize they know, or do they actually not know during these moments? This case seems unclear enough so as to allow a decision to b'e dictated by whatever larger view we take of knowledge. Thus I am prepared to say, and it does not grate heavily against my intuitions, that in so far as these skeptics have real, and not just hyperbolical, doubts about particular propositions they do not, when they have those doubts, know those propositions.

The pathological doorcheckcr is the fellow who frequently carefully and deliberately locks a door and then checks every few minutes to be sure that door is locked. Here it is supposed to be clear that the doorchecker knows the door in question is locked even though he reports that lie is constantly wondering to himself 'Did I lock that door?' The reason we, as observers, are tempted to say the doorchecl~er knows the door is locked is that it is perfectly clear to us that the door is locked and equally clear that the doorchecker has every right to believe that it is locked. Butwe are dealing with a pathological doorchecker. And what makes him pathological may well be that he has wholly unreasonable doubts about the states of doors he has just locked. 9 And I am prepared to say that in so far as he does doubt, however unreasonably, ,that a door is locked he also fails to know that that door is locked.

TEMPLE UNIVERSITY PHILADELPHIA, PENNSYLVANIA 19122

USA

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NOTES

See James Cargile's provocative article, 'Z)n Near Knowledge" , Analysis, vol. 31, 1971), for a similar observation, pp. 151-52.

James Cargile, Ibid., Harman has presented his view in a series o f articles and in his book, Thought (Princeton, N.J., Princeton University Press, 1973). The articles include: '~ Inference to the Best Explanat ion," The Philosophical Review, vol. 74 (1965), pp. 88-95, and "Knowledge, Inference, and Explanat ion," The American Philosophical Quarterly, vol. 5 (1968), pp. 164 173.

Harman ' s words are "inductive inference must take the form of inference to the best explanat ion and no explanat ion is involved in the lottery case." (APQ, p. 167.) But why is ~l'his ticket will lose because the odds against its winning are very high' not an explanat ion o f why the ticket will not win, assuming it does not win? For clarification we can look to Harman ' s claim that ' two things are necessary if an explanat ion is to be inferable. First, it mus t be much more probable on the evidence than its denial. Second, it mus t make what is to be explained more probable than its denial does ." (APQ, p. 169.) But `This ticket will lose because the odds against its winning are 10,000 to 1' seems to satisfy both these requirements . The purported explanat ion, ' the odds against its winning are 10,000 to 1', clearly makes what is to be explained more probable than does the denial o f this purported explanat ion. The purpor ted explanat ion, since it is simply a s ta tement of the evidence, is also much more probable on the evidence than is its denial. Perhaps there are other requirements which mus t be met before an explanat ion can be inferred, but if there are we are not told what they are. Alternatively, it may be that Harman simply thinks straight probability claims are not explanations at all, and hence trivially not inductively inferable explanations. Perhaps Harman thinks this because he wants to identify "what can be know with what can be inferred" (APQ, p. 168), and his intuitions, like mine, tell him we cannot know in the lottery case. But now the argument does seem to be objectionably circular. We cannot know because no inference to the best explanat ion is possible. No such inference is possible because no explanat ion is possible, and no explanat ion is possible because we cannot know. Note that a further consequence o f Harman ' s view is that 'This ticket will lose' is not only normally unknowable , but also not normally a reasonable object o f belief (because neither deduct ion, nor induct ion (construed as inference to the best explanat ion), will yield this proposition). The lottery paradox (this t icket will not win, and this ticket will not win, and . . . , so no ticket will win) is indeed avoided in this way. But the price for avoiding that paradox seems very high, especially in the absence o f a survey o f other possible ways to avoid it. We simply do very often move from 'It is very probable that p ' to p. While the view tha t in such cases we cannot thereby come to know p has considerable plausibility, the view that we cannot even have the reasonable belief that p is not similarly plausible. Th roughou t his writings on this topic Hat- man asks the reader to trust his in tut ions about what we would and would not say. And we simply would say the belief that John ' s ticket will no t win the Irish Sweepstakes is a reasonable belief. (See APQ, p. 164.)

3 3 8


4 See Thought, chapter 9.

s Harman considers a related case, that of a man who uses a barometer to predict rain. He has a false theory about why the barometer falls before rain (because of an increase in the force of gravity), but a true view as to the correlation between rain and a falling barometer. It is Harman's view that "The man in question has knowledge because he infers not only the stronger explanation involving gravity but also the weaker explanation. He infers that the explanation of the past correlation between falling barometer and rain is that the falling barometer is normally associated with rain. Then he infers that this weak generaliza~ tion will be what will explain the correlation between the falling barometer and rain in the next instance." (Thought, pp. 133-34.) Now we may be willing to countenance a great deal of unconscious reasoning, but surely not this much. The man in question could have so inferred a weak as well as the strong explanation, but there is no reason to think he does except that his doing so is rcquired to save Harman's position. People do not, at [east in their conscious reasoning, usually take care to formulate these kinds of weaker back-up cxplanations as insurance against the possibility of their strong explanations turning out wrong. Redundancy in explanation may be a good thing but this alone does not make it part of our actual practice in giving explanations.

6 Suppose John is in a coin toss with Sam and a three person lottery with two other friends. In each case the prize is a pink hundred dollar bill. The chances of John 's winning both the coin toss and the lottery are one in six. The chances of his losing both are two in six. And the antecedent chances of his winning the lottery are two in six. But if we know John has not lost both the coin toss and the lottery (we see him with a pink hundred) the chance of his having won the coin toss, which were one in two, become three in four. And the chance of his having won the lottery also improve, they are now one in two.

7 Apparently Cargile thinks his view sidesteps the Gettier problem simply by being ckcular. For Cargile, a justified belief is "a belief based on reasons (or other warrants) which arc good enough for the given sitm ation, that it qualifies as knowledge." (p. 146.) Since no Gettier case qualifies as knowledge, no Gettier case involves a justified belief. But this is hardly an interesting solution to the Gettier problem.

8 W.V.O, Quine and J.S. Ulliann, The Web of Belief (New York, Random House, 1970), p. 6.

9 I am indebted to Gary Thrane for this observation.

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in defense of not knowing

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