1. THE INFORMAL ARGUMENT

For every substantive argument or thesis I've ever come up with, throughout my career in philosophy, whenever I've pitched it to several people who are experts in the relevant field, at least some of them have found weaknesses in my position. It's not that they have refuted it, or that they even believe that they refuted it. Rather, they have presented me with an objection – to a premise, a conclusion, an inference – that I see is quite serious and that I have no real response to. This might happen all in one day, at a conference perhaps. Or, it might take several years. But talking with the other philosophers is usually unnecessary: on many occasions my own subsequent reflections have shown me the gaping holes in my prior ruminations. Things looked great back then; years later they don't look nearly as convincing.

Many of my arguments and views have not been subject to expert scrutiny. But I know, from two decades' experience with my positions that have been so scrutinized (by myself or others), that it's incredibly likely that the ones that haven't been examined by a decent set of experts including future temporal parts of myself – such as the ones I am constructing this year – would be found wanting in various important ways if they were so examined. And sure, some of them would escape unscathed if I didn't talk to too many experts or engaged in hyper-reflection. But past experience strongly suggests that in at least 90% of the cases in my future if I give a decent number of philosophical experts time to consider my argument or view, they will find problems that according to my own lights (and their lights) I won't deal with satisfactorily. In some cases in the past, if I had been confronted with certain specific objections I would have been happy to say in response to them that I was implicitly making an assumption that makes the objection miss its mark. (For instance, suppose I'm working on a theory of epistemically justified belief and an eliminative materialist objects that there are no beliefs: I would reply that I'm just assuming we have beliefs.) But the bothersome thought is that my actual experience, over many years, shows that for any argument I happen to come up with over the next few months, the odds are extremely good that there are serious objections that by my own lights I won't be able to block at all. This convinces me, or should convince me, that my arguments probably have all sorts of actual problems – serious ones – even if I know nothing about them. And if that's the case, then shouldn't I withhold my support of my arguments and theses? Shouldn't I ‘go agnostic’ on almost every substantive philosophical claim?

This is not to say that these experts (or my future self) laugh at my incompetent arguments from the past. It's not to say that with regard to past cases I eventually came to think, or they came to think, that my essay should not have been published. On the contrary, as I mentioned earlier I'm competent enough to publish almost all my essays in good journals: the referees and editors are happy to publish my work, and as far as I know no one is regretting the decisions (very much). But as we all know, such approval hardly indicates agreement with arguments or conclusions.

Several authors have put forth skeptical arguments about philosophy that turn on the notion of disagreement (e.g., Feldman Reference Feldman and Hetherington2005; Goldberg Reference Goldberg2009; Frances Reference Frances2010, Reference Frances, Lackey and Christensen2013; Fumerton Reference Fumerton, Feldman and Warfield2010; Kornblith Reference Kornblith, Feldman and Warfield2010, Reference Kornblith and Machuca2013).Footnote ¹ Those arguments are similar to mine in the sense that they are genuinely worrying. But the argument I am giving here nowhere demands that anyone disagrees with me. Unlikely as it would be, it could happen that everyone agrees with my philosophical thesis and even my argument for it. Alternatively, I might have received feedback from people I respect but they have not told me their opinion on the truth of my thesis; so I see the objections but I don't know what they make of them. Then again, maybe almost no one has thought about the (original) thesis; so it's not surprising that no one disagrees with me. But even so, induction on past cases shows that the odds are overwhelming that someone – myself or the relevant experts – would, given some time to think things through, still find serious problems with my argument or thesis. They might not think that the objections are serious enough to reject my thesis (e.g., the experts might think my argument is no good but a different argument for the same thesis is successful), so even in close possible worlds there need not be any disagreement. But given the way the actual world is, the odds are that I will end up seeing an objection that I realize I have nothing to say against and that I judge to be a serious challenge to my view.Footnote ² Even if I did all my philosophizing in utter isolation, in the style of a philosophical Robinson Crusoe, if I were reflective and honest with myself I would have eventually come to realize that there are major objections to virtually all my previous ideas – objections that I can't really deal with.

What my inductive argument and the recent skeptical disagreement arguments have in common is this: in each one, reflection reveals excellent evidence E1 that there is good evidence E2, usually argumentative, that goes against my philosophical views and is such that I don't have any good reason to think it's seriously flawed. Roughly put, in the disagreement skeptical argument my knowledge of the fact that a large number and percentage of my epistemic peers or superiors on the relevant topics disagree with me is excellent evidence E1 that there is good evidence E2 against my thesis – where E2 is evidence I won't have any answer to (by my own lights I will humbly realize that for all I can tell I have no defeater for E2). In the skeptical argument of this paper, induction on my past experiences – whether or not they have anything to do with disagreement – gives me excellent evidence E1 that there is good evidence E2 against my thesis – where E2 is evidence I won't have any answer to.Footnote ³

I am not saying that induction gives this result for everyone in philosophy. But it does for me, due in part to the fact that I am a merely average competent philosopher. If I were unreflective, then these reflections might be epistemically powerless. Or if I studiously avoided philosophers who will tell me what they really think. Or if I surrounded myself with only those folks who agree with me on just about everything of substance that I work on. Or if I were highly arrogant or otherwise supremely self-confident. But none of those qualifications apply to me. My argument in this essay applies to average competent philosophers who are highly reflective about their past philosophizing and/or who seek out honest opinions from a diverse group of competent philosophers – so they are firmly aware of their track records. Those who are not so reflective (should I say: not wise?) will be addressed in the final section.

2. PREMISES OF THE INDUCTIVE SKEPTICAL ARGUMENT

Thus far I have presented the inductive skeptical argument in an informal way, attempting to elicit the relevant intuitions. I hope that I have done enough to convince you that there is a real worry here; the informal argument looks like a serious challenge to the rationality of many philosophical beliefs. In this section I offer one precisification of the argument (you might formulate it differently). Here's the first premise.

1. (a) A large number of contemporary philosophers satisfy the following awareness condition: she is well aware that over the many years she has been doing philosophy, for almost every substantive philosophical thesis she publicly defended at least several years ago, there were objections to it back then that by her own current lights she was not, at that past time, able to block at all and that she currently judges to be serious in the sense that they supply significant evidence against her thesis.

The temporal element is crucial: premise (a) says that today you know of serious objections that existed back then and that you were unable to deal with back then. It doesn't say that you currently can't handle those objections. In many cases, if we are honest with ourselves we will realize that we still fail to have adequate responses to some of those objections. But the skeptical argument we are examining is silent on that matter.Footnote ⁴

What reflection on the past shows me is this:

Reflection on the past does not show me this:

That second remark would be nice if it were true, or even reasonable to believe. Its truth would mean I lived a charmed life when it came to philosophizing. Of course, once in a while things turn out grand: you come to believe T for moderately good reasons and then later discover some much better reasons that support T and defuse the objections to T. The inductive skeptical argument is saying, with premise (a), that things very often were not so wonderful.

What often happens is that one comes to believe a philosophical thesis at one time and then later, over the next couple of years say, one marshals more arguments for it. That's fine, but the skeptical argument I'm focusing our attention on is looking at the unmet objections.

Let me give a feel for the kind of reflections that typically make one satisfy the awareness condition in (a).

Naturally, (a) holds for only some philosophers. However, my hope is that it holds for many (e.g., at least half of philosophy professors). In most cases the serious objections to your past philosophizing that you can't handle are right there, waiting for you within relatively easy access, and if you haven't found them yet it's your own damn fault: you don't take your peer and superior philosophers seriously, you're unreflective, you are overconfident, or something similar and epistemically bad. Surely most philosophers are fully aware of the major objections to their views. If you are fully aware of them but are convinced that you defeated all of them years ago, then (a) doesn't apply to you. Later in the essay I will consider the epistemic position of (the considerable number of) philosophers who don't satisfy the awareness condition of (a).

If my experience is any guide, many philosophers are less likely to admit to the existence of serious unmet objections to theses that they have recently worked on compared with that for theses they worked on years ago (the longer the better). This is an empirical psychological hypothesis. That is why I used ‘at least several years ago’ in (a). This means that my inductive skeptical argument does not apply to people who have doing philosophy for a short amount of time; it is completely silent about them.

One might object to (a) by being skeptical of the power of philosophical objections: even though there is a host of objections to thesis T that the defenders of T can't parry, this hardly ever means that those objections supply strong evidence against T. This would be intended as a general statement about philosophical objections. I will not quarrel with that view. But look at what it means: if the arguments against T are so lousy that they supply no powerful evidence against it, then surely in the vast majority of cases it's also true that the arguments for T are so lousy that they supply no powerful evidence for it. (Here I'm assuming that T is not something utterly commonsensical such as ‘There are trees’, ‘I have two hands’, or ‘No contradictions are true’, which bring in special issues.) And that means that in most cases our philosopher didn't start out with a rational belief in T, before the awareness condition was satisfied.

In what follows I'll assume for the sake of a simpler argument that the critic of inductive skepticism about philosophy wants to argue that philosophers who satisfy the condition in (a) often have philosophical beliefs that start out rational and the philosopher is reasonable in sticking with them even though they satisfy the awareness condition.

When I say in (a) that the objections were ‘unmet’ I mean that by her own lights now, she didn't have a successful response to them back then – one that makes the objection lose almost all its force. Of course, there are plenty of philosophers who will insist, even publicly, that they successfully met all the many objections to their theses that have appeared over the years – despite the fact that a great many philosophers who have been paying close attention to the debate disagree with them on this score. Again the temporal element is important: all (a) is saying is that you didn't meet all the then-current serious objections to your thesis several years ago when you endorsed and defended it. Those confident philosophers who insist that they have always had adequate responses to all the objections to their believed thesis are not in the group characterized in (a), provided they have this confident attitude regarding most of their past philosophizing. I will address their epistemic position in the final section.

Often the objections to one's thesis are direct: they are attempts to show that such-and-such central claim is false. However, there are indirect objections as well – and as any seasoned philosopher knows these can be much more powerful. One is often confronted with collections of claims that attempt to do the same work as your theory – and you have no good reason for preferring your theory to the alternative.

One way to object to (a) is to argue that philosophers only very rarely believe their theses. I agree to an extent: we often defend ideas that we don't quite believe (e.g., I do it every day). An outsider might find this a bit odd. But in any case, I think it's pretty much beyond dispute that a great many philosophers do have plenty of substantive philosophical beliefs – firm ones, too.

On to the next premise of my inductive argument for skepticism:

1. (b) If the awareness condition in (a) is true of a particular philosopher, then she has excellent evidence E that for most any substantive philosophical thesis T she happens to believe today or tomorrow, there are objections to it that by her own lights she can't currently block and that she would judge to be serious in the sense that they supply significant evidence against her thesis.

This is the inductive premise: when it comes to serious unmet objections, what holds in the past holds in the present and immediate future. The idea behind (b) is that for the vast majority of people who satisfy the condition in (a), although our philosophizing may improve over the years it is unlikely it has improved enough so that the unmet serious objections no longer exist. That is, rejecting (b) means saying roughly this: although there were serious objections to past theses, there are far fewer of them for present or future theses.

Suppose a philosopher, after several years of ‘normal philosophizing’, becomes much more circumspect with regard to her philosophical beliefs: she only believes a philosophical thesis today when she judges the overall evidence to be utterly overwhelming in favor of it. As a consequence of this new belief policy, she no longer believes many of the views she once defended; and she comes to new philosophical beliefs only in extreme situations. She has changed her ways: before the change she believed that content externalism is true and trees are sums of merelogical simples; now all she believes is that trees might for all we know exist and people, if they exist, typically have cognitive processes.

This situation is irrelevant because as a matter of brute fact very few philosophers grow extremely cautious in their philosophical beliefs, confining them to theses such as ‘Humans probably exist and typically think on occasion’, ‘Trees probably exist’, ‘2 + 2 = 4’, and the law of non-contradiction.

It follows from (a) and (b) that our philosopher who satisfies the condition in (a) has excellent evidence E that for most any substantive philosophical thesis she happens to believe today or tomorrow, there are objections to it that by her own lights she can't block and that she would judge to be serious in the sense that they supply strong evidence against her thesis.

Assume now that despite the awareness described in (a) she continues to believe that her new philosophical thesis T is true. Assume further that she started with rational belief in or even knowledge of T (the latter being the most favorable case). Is her retaining of that belief in T – that doxastic action of hers made after becoming aware as in (a) – rational in the face of possessing evidence E, the evidence of current serious unmet objections? Our last two premises suggest not:

1. (c) Suppose (b) is true of a philosopher: she has excellent evidence E that for most any substantive philosophical thesis T she happens to believe today or tomorrow, there are objections to it that by her own lights she can't currently block and that she would judge to be serious in the sense that they supply significant evidence against her thesis. Suppose further that she retains her belief in thesis T despite having that evidence E. If her retaining of that belief is not seriously epistemically defective, then she must have had, at that past time, some epistemic item that ‘overwhelms’ E (where E is the excellent evidence she has that there are serious unmet objections to T).

2. (d) However, most philosophers who satisfy (b) had no such epistemic item for most of their theses.

Premise (c) is saying that in order for her retaining of her belief to be rational she needs to have had, at about the time of retention, an argument or piece of evidence or reliability fact or some other epistemic item that keeps this belief rational despite her possession of E. There are several obvious candidates for such a wonderful, rationality-saving epistemic item.

For instance, perhaps unlike most cases in the past, this time around she really does have an adequate argumentative counter to every serious objection to her new thesis T; the collection of those counters might be a sufficient epistemic item that (c) talks about. Or, maybe God has told her that all the objections to T stink; his word could be the epistemic item. Or, perhaps she knows that virtually all of her objectors are wildly biased against her ideas for poor reasons. Or, perhaps she just has so much evidence for T that even though she lacks a counterargument to the objections – she hasn't the foggiest idea what to say in response to them – her original evidence is strong enough to make her belief retention rational; that towering body of evidence for T could be the epistemic item that suffices for her belief retention to be rational. Those are four examples of adequate epistemic items.

In order to understand the last example, think of how a mathematically weak person knows full well that 1 ≠ 2 even though he is aware of a ‘proof’ that 1 = 2 in which he can't find an error (the ‘proofs’ usually divide by zero at some point, but in a way hidden to people who don't have much mathematical skill; see youtube.com for examples). His evidence for 1 ≠ 2 is so good that it doesn't matter, to the rationality of his belief retention, that he can't find any error in the sophistical ‘proof’ that 1 = 2. Well, perhaps such a scenario could happen in ordinary philosophical research as well, although this seems like a very rare scenario at best (e.g., our evidence for the existence of baseballs is so good that we are rational in retaining our baseball beliefs even though we are aware of, but have no argumentative counter to, the arguments of physicists and metaphysicians that there are no composite objects).

Therefore, in premise (d), with the use of ‘in most cases’, I am being friendly to the anti-skeptic in allowing for all sorts of epistemic items that can ‘overwhelm’ E (e.g., ‘overwhelm’ does not mean refute, in an argumentative sense) enough so that the believer in question is rational in sticking with her belief in T. Furthermore, some epistemologists would insist that she has to be aware of the epistemic item that suffices for the rationality of the belief retention; others will say she doesn't need that awareness as long as the item exists. In order to give the anti-skeptic the best chance, I'll assume there is no awareness condition.

Premise (c) uses a notion of belief retention that is ‘seriously epistemically defective’. On one notion of epistemic defectiveness, for instance stupidity, I think (d) is false: the typical philosopher has enough warrant, or at least reasonably apparent warrant, for her retaining of her substantive philosophical beliefs to not be stupid even if she satisfies the awareness condition in (a).

One could characterize a notion of epistemic defect that lies at the other end of the epistemic scale: the belief retention is epistemically defective merely in the sense that a perfect epistemic agent would have done better than retain belief in T. If so, maybe (d) ends up true but then the conclusion is probably not very interesting.

One can offer several proposals here as precisifications of ‘seriously epistemically defective’, but here is the one I will use in this essay: when the inductive skeptic says our retaining our substantive philosophical beliefs is ‘seriously epistemically defective’ she means that at the very least, charges such as ‘You know better than to do that’, ‘You are being a bit foolish’, and ‘You would be much more reasonable to suspend judgment on T’ apply to the person in virtue of her retaining the philosophical belief.

That's my brief clarification of ‘seriously epistemically deficient’. You could assess the inductive skeptical argument using other conceptions of epistemic rationality: we get different arguments for different conceptions.

Inductive skepticism follows from (a)–(d):

1. (e) If a philosopher satisfies the condition in (a) and retains her belief in T, then in a large number of cases her belief retention is seriously epistemically defective.

3. PREMISE (C) OF THE INDUCTIVE SKEPTICAL ARGUMENT

I will consider two ways of objecting to premise (c), and one of them will lead to a modification of the conclusion (e). The first (and long) objection starts as follows.

Suppose you want to investigate some philosophical thesis T, perhaps the content internalist thesis that belief contents strongly supervene on the believer's internal physical makeup. There are two categories of considerations you might look to in figuring out what to think about T:

Suppose next that you evaluate in a professionally competent manner the direct stuff in (1) in the following sense:

• • You do about your best in evaluating the stuff in (1).

• • Your approximate best is about the same, very roughly, as the approximate best of most other philosophy professors around today.

• • You evaluate virtually all of the publicly available stuff in (1).

• • Other philosophy professors would respect your evaluation even if they didn't agree with it (respect in the sense that they would have no problem recommending you for tenure).

Now note that in our profession the deliberation practice is this: in our deliberations devoted to figuring out whether a thesis such as T is true, we look almost exclusively to the stuff in (1). Further, it is our assertive practice to assert the conclusions of our deliberations. That's just the way philosophers operate; that's the way things are done around here.

Finally, the critic of (c) gives some reason R why the combination of (i) professionally competent evaluation of T and (ii) the natures of our deliberative and assertive practice pretty much guarantees that one's view on T is epistemically rational. I don't know what R would be, but let's be generous and assume that R is a plausible one; that way, we are giving the critic of (c) the benefit of the doubt.

The critic concludes from her premises including R that a great many of the cases of philosophical belief covered by premise (a) will be professionally competent and hence epistemically reasonable even without any epistemic item that overwhelms E. In brief, if you have done a professionally competent job and just about everyone treats you as being epistemically reasonable, well that is usually sufficient for actually being epistemically reasonable even if you have nothing up your sleeve that deals with the evidence E that premise (b) talked about. Thus, premise (c) is false: no epistemic item is needed for rational belief retention.

If the critic's view is that we are rationally required to retain belief, then the view is suspect: wouldn't it be rational to suspend judgment or at least severely reduce one's level of confidence? If the critic's view is that it is rationally permitted to retain belief – but suspension is also rationally permitted, perhaps with a lower degree of rationality – then her view is more reasonable.

I think the objection is right on a couple of matters: it accurately describes our deliberative and assertive practices. It is our practice to assert all sorts of controversial claims even when we satisfy the awareness condition in (a). At least, what we are doing when we say things like ‘Content externalism is true’ certainly seems very much like assertion, even if it's not exactly assertion. And this seems like a reasonable way to carry out the practice of philosophy.

However, I have doubts that there is a smooth transition from professionally acceptable assertion to epistemically reasonable belief. In particular, I suspect the objection fails right where it needs to work: for the cases mentioned in (a). Perhaps professionally competent evaluation is almost always sufficient for reasonable belief when one doesn't satisfy the awareness condition in (a):

But once a person satisfies that condition (and they haven't radically changed their ways, as discussed in the previous section), the material in the Indirect Category becomes obviously relevant to one's rationality in holding T. Indeed, the awareness condition is exactly the type of thing that is in that category! In meeting the awareness condition you have become aware of a threat to your current views. Perhaps when you are ignorant of that threat – or have grown old and professionally comfortable enough to forget it – it doesn't provide an epistemic hurdle to rationality. Now it does.

There is another problem with the objection to (c): if it fully succeeds, then all this shows is that epistemic rationality is cheap and subpar: (i) the standards for rationality are much less impressive than we thought (that's cheap) and (ii) we can do much better by suspending judgment (that's subpar). If the objection to (c) is sound, well then so much for rationality: philosophers have been chasing a notion that is not nearly as impressive as we thought it was. It would be like discovering that knowledge is just true belief that isn't violently stupid. If that's all knowledge comes to, then it's somewhat embarrassing that we have been puzzling over knowledge for well over two thousand years.

If one wants to be generous to the critic of (c), then one could change (c) and (e) as follows ((d) need not change):

1. (c’) Suppose (b) is true of a philosopher. Suppose further that she retains her belief in thesis T despite having that evidence E. If her retaining of that belief is not seriously epistemically defective, then either she must have some epistemic item that ‘overwhelms’ E or her retaining that belief isn't seriously epistemically defective but is epistemically unimpressive and we can do much better by suspending judgment.

2. (e’) If a philosopher satisfies the condition in (a) and retains her belief in T, then in most cases her belief retention is seriously epistemically defective or it isn't seriously epistemic defective but her belief retention is epistemically unimpressive and we can do much better by suspending judgment.

The second (and much shorter) objection to (c) is that since (a), (b), and (d) are true, premise (c) sets a standard that if followed would lead to epistemic disaster for philosophy. If we had to suspend judgment practically all the time in philosophy – which is what we would have to do if (a)–(d) were true – then we simply would not be able to philosophize with much passion at all. And without passion, our profession would die.

I think this objection makes a key mistake: it's actually not that hard to do philosophy with real passion even though one suspends judgment on one's theses. Furthermore, the objection either is a non-sequitur (it never even says that (c) is false) or posits a highly controversial connection between epistemic success and epistemic rationality (claiming that if X leads to epistemic disaster, then X is epistemically irrational).

4. THE LAST PREMISE

Premise (d) says that the philosopher who meets the condition in (a) in most cases fails to have any epistemic item that overwhelms E so that her retaining her belief in thesis T is rational. In this section I defend (d).

As I mentioned in section 3, the philosopher who satisfied the awareness condition in (a) could have adequate counterarguments to every objection, and she could have started out with so much evidence for her belief in T that even if she doesn't have the counterarguments, her belief retention is rational. But the inductive skeptic says that in the large majority of cases neither possibility is actual; that's the reason for the use of ‘in most cases’ in (d). The skeptic says that it's unlikely for an average run-of-the-mill philosopher to be so fortunate in those two ways (having adequate counterarguments, having a colossal amount of evidence to begin with). Sure, on occasion such a philosopher has genuine, full-fledged knowledge of one's substantive philosophical thesis – let us be highly optimistic – and this knowledge is so powerful and tenacious that retaining the belief is rational even in the face of evidence that there are unmet serious objections to it. But this isn't true very often. For one thing, there are other philosophers who meet the condition in (a) who believe ~T: they don't have knowledge, so they don't have tenacious knowledge.

There are two ways to criticize (d). What they have in common, of course, is this: the philosophers who satisfy the condition in premise (a) typically do have epistemic items that suffice for the rationality of their retaining their belief in their substantive philosophical theses. The two criticisms differ in what they say about the philosopher's past. On the first criticism, her present isn't like her past: now she has the sufficient epistemic items even though she didn't in the past. On the second criticism, her present is like her past in that in both time periods she has had epistemic items sufficient to overwhelm E and thus protect her belief retention from serious epistemic deficiency. I will address the criticisms in reverse order.

The scientific analogue of the inductive skeptical argument suggests that the second criticism fails. To see this, note first that the best scientific analogy for the philosophical unanswered substantive objections is recalcitrant experimental data. Suppose you come up with an intelligent scientific hypothesis that is supposed to deal with a certain phenomenon but then you discover that researchers have collected significant data sets that go against your hypothesis. Perhaps your theory predicts a temperature of 878 Celsius but all the extensive data come in the range 830–835. Of course, this doesn't flat out refute your hypothesis. Perhaps the experiments that generated the data were faulty. Or maybe the interpretation of the data was faulty (e.g., the experiments didn't really give a temperature range of 830–835 or your hypothesis doesn't really predict 878 in this particular case). There are multiple ways the recalcitrant data could fail to refute your hypothesis. If you had good reason independent of your hypothesis that the data were faulty, or that the data were fine but perfectly consistent with your hypothesis (contrary to what others have thought), then you could be rational in sticking with your belief in P. But if you realized that you had no independent grounds for thinking something has gone amiss with the data or the interpretation, then you'd be a fool to stick with your hypothesis unless there were a huge mountain of confirming data that swamped the contrary data. This ‘mountain of confirming data’ scenario is the scientific analogue of the philosophical situation in which there is a fantastic body of evidence for your thesis and only a couple of odd objections (e.g., perhaps this is the case for the law of non-contradiction or the thesis that there are baseballs). But if you don't have a staggering mountain of evidence for your thesis and you have no independent grounds for rejecting all the objections to your thesis – a common scenario in philosophy, for sure! – then you should withhold judgment on T, just like in science when you don't have a mountain of confirming data or independent reason to reject the data.

However, what if I formed my belief in philosophical thesis T in a highly reliable fashion? In fact, what if I actually know T before I think about or discover the objections? Shouldn't that count for something? In particular, doesn't the basis for that knowledge serve as an adequate ‘epistemic item’, the very thing premise (d) says we usually don't have?

I think there might be something to this line of thought (cf. Thomas Kelly's ‘Total Evidence View’ in his Reference Kelly, Feldman and Warfield2010). If you know T, and you know it in some epistemically impressive way (so it's not just ‘animal’ knowledge for instance) but are then presented with objections to T that you can see are serious and that you know you have no real reply to, then if you stick with your belief in T, then perhaps that retained belief is rational. I doubt it, but suppose it's true. Even so, I don't think it will help much in our attempt to object to (d). The main reason is that in order for it to help we have to start out with impressive knowledge of T. Clearly, this isn't going to happen very often, as there are plenty of false philosophical theses endorsed by the philosophers who meet the awareness condition in premise (a). Moreover, even setting aside that problem, those of us with true substantive philosophical beliefs often don't start out with impressive reflective knowledge of them.

Let's move on to the first criticism. I think it is weak, at least for many of us, as it is saying that the philosophers who satisfy the condition in (a) typically are in a much improved epistemic state regarding their philosophical beliefs: although in the past they didn't have epistemic items sufficient to parry all objections, now they do. (Or, they don't have that ability now but unlike in the past nowadays they have evidence for their theses that is so overwhelming that the ability isn't needed in order to have rational belief retention.) This might be true for some of us: you could just become extremely circumspect in your philosophical beliefs, thereby making (d) false yourself. But there are many philosophers who are not so fortunate or circumspect.

However, there is a concrete way to fill out the first criticism so that it's strong. Suppose you come to think that when you first start defending a substantive philosophical thesis, there are serious objections to it that you just can't block at all. So you meet the awareness condition in (a). But further inductive reasoning rescues you! Reflection on your past leads you to justifiably think that in the past it almost always turned out that you eventually found adequate ways to block all the objections. So, sure, at the beginning you may have been unjustified in your philosophical belief, but history shows that eventually, given time, your belief became justified. And now you can say to yourself ‘There probably are serious objections I can't handle right now, but the odds are excellent that I'll be able to deal with them down the road; so I can stick to my belief knowing that eventually I'll be able to adequately handle the objections’.

Hence, this further insight into your past – your excellent track record in eventually coming to have adequate responses to the previously unmet objections – is the ‘epistemic item’ that suffices for your present belief retention to be reasonable. You didn't have it before, as you hadn't reflected properly, but now that you have it you are reasonable in retaining your current philosophical belief.

I see a few minor problems with this response. First, even if you have such a favorable track record, you may well not think of it; and if so, it is difficult to see how much epistemic weight it may have in neutralizing the effect of the awareness condition in premise (a). Second, it is going to serve as the adequate epistemic item only if you justifiably think your track record in coming up with adequate responses to the objections is excellent; such a justification might not always be present. Third, I think that in most cases one does not have a favorable track record, for the following reason.

Earlier I made a distinction between direct and indirect objections. The latter are the killers: they are the ones that are the hardest to respond to. You may have a well-thought out theory of X, and you may have intelligent responses to objections to various parts of your theory, responses that can hardly be refuted. But the hard part is offering some reason to think that your theory is true while the competitors are false. Eventually most of us realize that as wonderful as our favorite theories are, the rivals can tout comparable virtues and suffer from comparable vices. Their mere existence on the philosophical shelf of theories constitutes an indirect objection, one that is very hard to deal with. So that's why I think that most of us do not have adequate responses to objections.

However, in spite of all that I suspect that in many cases the response works at least in this sense tied to praise and blame: there are a significant number of philosophers who meet the awareness condition of premise (a) who also sincerely and blamelessly – if mistakenly – think that in almost all cases in their past they eventually came to be able to block all the serious objections to their substantive philosophical views.

Nevertheless, I think this response is not available to – how do I say this nicely? – philosophers who aren't so clueless.

To see why, imagine that you're a philosopher of language who is researching theories of propositions. Perhaps you are weighing in on the issue of whether propositions contain concrete objects or mere representations of such objects. One of your assumptions is that there are propositions to theorize about. And yet, you had no way to block the standard objections to the idea that propositions exist. Over the years what usually happens is that one slowly realizes that this is one of those issues that is stubbornly up for grabs and there just isn't any clear winner of a position, nominalist or realist. You realize that although you have things to say in favor of the existence of propositions, you cannot block the arguments to the contrary. When it comes to many of the big issues, you fall on one side, others fall on the other side, and no one has anything even remotely like a decisive argument to back themselves up.

At this point I think most philosophers who have this realization change their beliefs: they conditionalize them. With regard to the above example, instead of defending thesis T about propositional structure, one now believes ‘If A, then T’, where the antecedent is something like ‘There are propositions and they have both structure and constituents’. Alternatively, one's thesis has gone from T to something like ‘Setting aside those recalcitrant objections, T’. In either case, one no longer believes T and has a much more modest belief in its place.

5. EPISTEMIC NEGLIGENCE AND EXCUSE

Thus far I have focused on philosophers who meet the awareness condition in premise (a): aware of the fact F that over the many years she has been doing philosophy, for almost every substantive philosophical thesis she publicly defended at least several years ago, there are objections to it that by her own current lights she was not, at that past time, able to block at all and that she currently judges to be serious in the sense that they supply significant evidence against her thesis. But what about those who are not aware of fact F – even though F really is a fact about her?

I'll look at just two ways a philosopher might fail to recognize F: she has simply not reflected on the matter, and although she has reflected on it, she is convinced that F is false.

Often enough, someone is to blame if they overlook something that they shouldn't have overlooked. Perhaps in most cases a philosopher is blameworthy if she fails to realize that ‘over the many years she has been doing philosophy, for almost every substantive philosophical thesis she publicly defended at least several years ago, there are objections to it that by her own current lights she was not, at that past time, able to block at all and that she currently judges to be serious in the sense that they supply significant evidence against her thesis’. Given that she is an experienced and reflective philosopher, and the objections are standing right before her, she should not overlook them; she is epistemically negligent if she does overlook them.

I'm not saying that her retained belief will be blameworthy. And I'm not even saying that the retaining of that belief is blameworthy. Thus, I'm not saying that she falls prey to the inductive skeptical argument. For all I know she escapes that argument entirely. Instead, I'm suggesting that if she does evade that argument, she most likely does so by committing some other epistemic sin (one of overlooking what one epistemically should not overlook – in this case, the fact F).

A similar point holds for those who upon reflection falsely deny F. I have in mind the philosopher who will make remarks such as ‘Well, the objectors to my thesis T are just hopelessly biased or the victims of current philosophical fashion that is simply baseless’. Now, if such remarks are overall justified, then the philosopher escapes blame entirely: not only does she avoid the snare of the inductive skeptical argument (by falsifying premise (a)) but she does so blamelessly (so the negligence charge discussed immediately above doesn't apply to her). At least, I'm willing to allow that possibility. However, in a great many cases such remarks will be unjustified. The large number of philosophers who reject T after thinking hard about it are no more biased than the advocate of T, and the ‘fashion’, if it exists at all, may well be based almost entirely on good arguments, not anything like whim. So this philosopher escapes the inductive skeptical argument (by falsifying (a)) but may well fail to avoid epistemic sin in doing so.

6. THE SCOPE OF THE ARGUMENT

Thus far I have focused on the philosophical beliefs of philosophers that they defend in their work. It is not an argument against philosophical beliefs in general, even those of philosophers. It is an argument that applies solely to the thesis-products of one's professional investigations, which have occurred over many years.

When we modify the argument to apply to other professional beliefs, premise (a) looks like this:

I think this premise will be false for most scientists regarding their research.Footnote ⁵ The typical scientist is not ‘well aware’ that in the past there were objections to her work that she had no way to block. A large portion of science is the uncontested accumulation of facts or ‘results’ (take a look at some science books for children, or the more experiment-based journals); speculative theorizing – actually, any theorizing at all – is a lot rarer than in philosophy. Of course, this depends on what kind of scientist one is! If a scientist restricts her publishing to a place such as Foundations of Physics for instance, then she is doing a lot of highly speculative research. But an enormous part of science isn't like that at all. When premise (a) is true of one's work, then of course the argument proceeds as before.Footnote ⁶