External Factors and Evidential Symmetry

I'm thinking about the relationship between factive reasons and internalism.

A certain gumball machine has two possible modes. In mode A, it delivers blue gumballs with 90% probability, and red gumballs with 10% probability; in mode B, those proportions are reversed. (The probability for each gumball is independent.) Every morning, a fair coin is flipped to determine in which mode it will remain for the duration of the day. Vibhuti knows all of this. She begins our story with an epistemic probability of .5 for proposition h.

h: the machine is in mode A.

Now two of Vibhuti's friends who have been to the gumball machine today come along. Tunc tells her that he bought a gumball, and it was blue. (This is evidence in favour of h.) Eric tells her that he bought a gumball, and it was red. (This is evidence against h.) Tunc and Eric are equally (and highly) honest and reliable (and Vibhuti knows this). The evidential situation looks entirely symmetric, so Vibhuti's evidential probability for h looks still to be .5.

But certain approaches to evidence might disrupt this apparent symmetry. Suppose it turns out that Eric is lying, but Tunc is telling the truth, and indeed, reporting something he knows. (We've stipulated that this is unlikely, but not that it's impossible.) The lie is skillful, and Vibhuti isn't suspicious; she very reasonably takes both of their assertions at face value. Let's also take on board the following epistemic assumptions (if only to see where they lead):

1. Testimony almost always puts one in possession of knowledge of the fact that the testimony occurred.
2. Testimony at least sometimes puts one in possession of knowledge of the fact testified.
3. E=K.

(Note that I am not assuming a reductivist approach to testimony; there's no claim that the knowledge from 2 typically or ever is based on the knowledge from 1.)

Given these assumptions, it looks like we may not get Vibhuti's case as symmetrical after all. Although she has some evidence in favour of h and some against it, it isn't all symmetrical. For it looks like her relevant evidence is the following:

• Tunc says he got a red one.
• Tunc got a red one.
• Eric says he got a blue one.

The first and third on this list look to be symmetrical for and against h. But the strongest item here counts unambiguously in favour of it. You might think that the second swamps the first in evidential relevance—that sort of seems right—if so, then we could just look at this list:

• Tunc got a red one.
• Eric says he got a blue one.

Here we have one piece of evidence in each direction, but the first item, which counts in favour of h, looks stronger than the second. So it looks like there's going to be some pressure against the idea that Vibhuti's evidential probability in h is .5; it seems like it should be higher than .5.

So how, if at all, could E=K (and really, the challenge applies to a broader range of views: anyone strict enough to demand true evidence, but lax enough to allow testimonial contents sometimes to be evidence) accommodate the apparent evidential symmetry in cases like this? I see four options.

1. Deny that one can ever get the contents of testimony as evidence, because we don't really know the things we're told, even when we're told by people who know. (Skepticism about testimony.) This might be more palatable than it seems if accompanied with some kind of contextualism about both 'knows' and 'evidence'.
2. Deny that one can ever get the contents of testimony as evidence, because not all knowledge is evidence—maybe only direct or basic knowledge counts as evidence. (E=BK)
3. Deny that in particular cases like this one can get knowledge via testimony. If one friend is lying to you, then you're in a skeptical situation where testimony is unreliable. (But will this solution be general enough?)
4. Admit everything I've said about what evidence Vibhuti has, but argue that, for purposes of evidential probability, the situation is symmetrical after all. (The relationship between evidence and evidential probability is complex; I'm really working with something of a 'black box' for the latter—must we suppose that the black box delivers the assymetrical verdict in a case like this?)

Maybe there are more, I'm not sure.

Philosophical Assertions

Chapter 9 of Sandy Goldberg's recent book Assertion argues, on the basis of peer disagreement in philosophy, that it characteristic of typical, apparently appropriate, philosophical discussions that they include many assertions of contents for which the speakers are not justified. This is part of a bigger case that the epistemic norms governing assertion do not always make for strong epistemic constraints.

I am not convinced that the cases of disagreement he's looking at are cases in which people are typically making out-right assertions of controversial contents. I am attracted to something like the idea he recognizes in this passage:

I have sometimes heard it said (in conversation) that there really are no straight (first-order) assertions of controversial matters in philosophy, only speculations and conditional (or otherwise hedged) claims. A characteristic claim in this vicinity is that philosophers do not flat-out assert their claims, but instead suggest them tentatively, or with something like a "we have some reason to think that" operator in front of them. (p. 247)

I would weaken this point slightly—perhaps philosophers do sometimes assert things that they can't justifiably believe because of considerations about peer disagreement, but hold that these assertions are inappropriate norm violations. If most of the time, including all of the times that are clearly appropriate, philosophers are doing something weaker than flat-out asserting, then his larger argument for a weaker assertion norm doesn't really get off the ground. (While it may be unacceptable to suppose that philosophy is absolutely full of unwarranted assertions; it seems to me not at all implausible to suppose that some philosophers sometimes make unwarranted assertions.) But I do think that philosophers often tend to exaggerate the strength with which philosophers tend to put forward their philosophical ideas.

In response to this move, Sandy writes the following in defence of 'PASD'—the claim that it is common for philosophers in cases of systematic peer disagreement to assert controversial claims. This is a continuation of the passage quoted above:

I agree that this is sometimes the case. But I find it dubious in the extreme to think that all cases of apparent assertions made in philosophy under conditions of systematic peer disagreement are like this. Surely there are some cases in which a philosopher continues to assert that p, despite the systematic p-relevant peer disagreement. (fn: Indeed, some philosophers have even conceded as much in their own case.) Here, two points of support can be made. First, it should be obvious to anyone who has participated in or observed philosophical practice that there are (some, and arguably many) occasions on which a claim is advanced under conditions of systematic peer disagreement without any explicit hedge or "there are reasons to think" operator in play. For this reason, if the hedging proposal is to work, it must postulate an implicit (linguistically unmarked) hedge or "there are reasons to think" operator in play in all such cases. But such a global postulation would appear to be fully theory-driven, and so ad hoc. What is more (and this is my second point), there are independent reasons to think that such a postulation is not warranted. In particular, the suggestion—that philosophical practice under conditions of systematic peer disagreement always involves hedged rather than straight assertion—appears to be belied by other aspects of our practice. Why the vehemence with which some (apparently first-order, categorical) philosophical claims are made, even under conditions of systematic peer disagreement? Why so much heat, if all we are doing is entering hedged claims? Why do we go to such great lengths to try to defend our claims in the face of challenge? Why not shrug off such challenges to our claim that p, with the remark that, after all, we were merely claiming that there are reasons supporting that p? Relatedly: why is it that the typical response to challenges is to try to defend the claim that p, not the (weaker) claim that there are reasons to believe that p? Finally, if all we are doing in philosophy is entering hedged claims, why is talk of our philosophical "commitments" so prevalent? Reflecting on this practice, I conclude that assertions are made in philosophy, even in the face of systematic peer disagreement. PASD is true.

I want to make three observations about this argument. First, for the reasons mentioned above, I think that Sandy is wrong to focus on the question of whether philosophers ever make assertions of controversial claims. For his argument to work, he needs this to be common enough that the verdict that such claims are unwarranted is undermining of philosophical practice. Second, he seems to be focused primarily on the idea that philosophers are asserting something weaker, like an existential claim about reasons; a more promising version of the idea seems to me that we are often making weaker commitments to categorical philosophical contents—that we're often speculating that p, for instance, rather than out-right asserting it. (Sandy recognizes that there is an important distinction here elsewhere in the book.)

Third, I think that when we really get down to what philosophers actually say and write, outright assertions of contentious claims are much rarer than we sometimes suppose. We very often use 'it seems to me that' etc. hedges. I think the passage I've just quoted from Sandy is reasonably representative in terms of philosophical force and style—but how often does it contain actual assertions of contentious claims? Let's look in detail:

• I agree that this is sometimes the case. May or may not be an assertion, but if it is one, it's an uncontroversial one Sandy makes about himself.
• But I find it dubious in the extreme to think that all cases of apparent assertions made in philosophy under conditions of systematic peer disagreement are like this. Ditto.
• Surely there are some cases in which a philosopher continues to assert that p, despite the systematic p-relevant peer disagreement. To my ear, the 'surely' makes this an invitation to notice for oneself, not an outright assertion. (I can almost hear question-marks on 'surely' claims.) But if it is an assertion it's a very weak one, and not one I'd expect to see systematic disagreement about.
• Indeed, some philosophers have even conceded as much in their own case. An assertion, but not a contentious one.
• Here, two points of support can be made. Ditto.
• First, it should be obvious to anyone who has participated in or observed philosophical practice that there are (some, and arguably many) occasions on which a claim is advanced under conditions of systematic peer disagreement without any explicit hedge or "there are reasons to think" operator in play. Plausibly an assertion, but not controversial.
• For this reason, if the hedging proposal is to work, it must postulate an implicit (linguistically unmarked) hedge or "there are reasons to think" operator in play in all such cases. An assertion. If 'the hedging proposal' is the idea that philosophers never make assertions in these cases, it looks like an uncontroversial one; if it's the more general idea that one can avoid his argument by invoking hedging moves, I think it's an unwarranted assertion for the reasons mentioned above.
• But such a global postulation would appear to be fully theory-driven, and so ad hoc. Exhibits the kind of hedges he's talking about.
• What is more (and this is my second point), there are independent reasons to think that such a postulation is not warranted. Exhibits the kind of hedges he's talking about.
• In particular, the suggestion—that philosophical practice under conditions of systematic peer disagreement always involves hedged rather than straight assertion—appears to be belied by other aspects of our practice. Exhibits the kind of hedges he's talking about.
• Why the vehemence with which some (apparently first-order, categorical) philosophical claims are made, even under conditions of systematic peer disagreement? Why so much heat, if all we are doing is entering hedged claims? Why do we go to such great lengths to try to defend our claims in the face of challenge? Why not shrug off such challenges to our claim that p, with the remark that, after all, we were merely claiming that there are reasons supporting that p? Relatedly: why is it that the typical response to challenges is to try to defend the claim that p, not the (weaker) claim that there are reasons to believe that p? Finally, if all we are doing in philosophy is entering hedged claims, why is talk of our philosophical "commitments" so prevalent? Six rhetorical questions provided to invite the reader to share in the appearance mentioned in the previous point. No assertions here.
• Reflecting on this practice, I conclude that assertions are made in philosophy, even in the face of systematic peer disagreement. Not obviously a contentious assertion. It could be an uncontentious assertion about Sandy. It could be the very weak assertion that assertions are sometimes made in philosophy under systematic disagreement.
• PASD is true. Looks like a contentious assertion; I'd be willing to call it unwarranted, because of the objections mentioned above. (PASD is a claim about what is normal; the existential doesn't justify it.) Note also that this could be interpreted as embedded within the previous sentence's 'I conclude that' operator, in which case it would not be a contentious assertion.

Again, I don't think Sandy's writing here is idiosyncratic; this is what lots of analytic philosophy looks like. If this is representative, it seems that quite a small proportion of philosophical writing constitutes outright assertion of contentious claims. So the idea that such assertions are unwarranted does not imply that warranted philosophical dialogue and debate is impossible. Sandy exaggerates the role of contentious assertions in philosophical discussion.