LOGOS & EPISTEME, VII, 1 (2016): 95-100 JUSTIFICATION AND THE UNIQUENESS THESIS AGAIN – A RESPONSE TO ANANTHARAMAN Luis ROSA ABSTRACT: I reinforce my defense of permissivism about the rationality of doxastic attitudes on the face of a certain body of evidence against criticism published in this journal by Anantharaman. After making some conceptual clarifications, I manage to show that at least one of my original arguments pro-permissivism is left unscathed by Anantharaman's points. KEYWORDS: uniqueness thesis, epistemic rationality, permissiveness In "Justification and the Uniqueness Thesis" (published in this journal),1 I argued that the following claim is false: for any proposition p and body of evidence E, there is at most one type of doxastic attitude that is rational for one to take toward p on the basis of E. This is the so-called 'uniqueness thesis.'2 In the original arguments, I used considerations about cognitive limitation (possession or lack of inferential abilities) in order to motivate the following claims: (i) there are situations in which the attitude of belief and the attitude of suspension of judgment would both be rational attitudes for one to take towards p given one's evidence E, and (ii) there are situations in which the attitude of belief and the attitude of disbelief would both be rational attitudes for one to take towards p given one's evidence E. Call the former the 'moderate permissiveness thesis,' and the latter the 'extreme permissiveness thesis.' Both the moderate and the extreme permissiveness theses are inconsistent with the uniqueness thesis. My case against the uniqueness thesis was recently criticized by Muralidharan Anantharaman (also in this journal),3 who purports to defend a particular version of that thesis against my objections. He does so by appealing to what he calls a "non-deontic account of rationality."4 Before I address 1 Luis Rosa, "Justification and the Uniqueness Thesis," Logos & Episteme III, 4 (2012): 572-574. 2 See Richard Feldman, "Reasonable Religious Disagreements," in Philosophers Without Gods, ed. Louise M. Antony (New York: Oxford University Press, 2007), 205. 3 Muralidharan Anantharaman, "Defending the Uniqueness Thesis: A Reply to Luis Rosa," Logos & Episteme VI, 1 (2015): 129-139. 4 Anantharaman, "Defending the Uniqueness Thesis," 130. Luis Rosa 96 Anantharaman's objections, however, let me make some important preliminary points – some of which I believe were not sufficiently clear in the original paper. First and foremost, the uniqueness thesis I take to be false is not a thesis about sheer evidential support. It is rather a thesis about ex ante justification/rationality (as opposed to ex post or doxastic justification/rationality): it is about the range of doxastic attitudes that one is entitled to form given one's available evidence (whether or not the subject has already formed the relevant doxastic attitudes). To be sure, it may be false that there is at most one type of doxastic attitude that is rational for one to take toward p given one's evidence E while it is still true that E either gives sufficient support to p, or to not-p, or it is neutral with respect to p – where neither of these disjuncts is compatible with the others. Second, I take it that the truth-conditions for attributions of ex ante justification or rationality should not abstract away from human's cognitive capacities. Believing that p is ex ante justified or rational for S when and only when S is epistemically entitled to believe that p. But a subject is not entitled to believe that p on the basis of certain body of evidence E when she is not able to do so competently. That is: no one is epistemically entitled to form a belief in the wrong way, even if one has evidence that gives overall support to the propositional content of that belief.5 E.g., even if a certain complicated theorem T follows from one's available reasons, it might not be rational for one to believe that T: it may be the case that the only ways one can come to believe that T using one's available reasons are epistemically bad ways. In that case, given one's situation, one is not entitled to believe that T, for if one were to believe that T one would do so in the wrong way. So I submit that it is rational or justified for a subject S to believe that p, given S's evidence E, only when S is able to believe that p on the basis of E in the right way (or S is able to competently believe that p on the basis of E). What is the right way of forming a belief on the basis of certain reasons? There are at least two things we can briefly say about this here. First, a belief is formed on the basis of certain reasons in the right way only when the relevant process is an instantiation of a reliable type of process. I.e., if one's belief Bq is based on one's beliefs Bp1,..., Bpn in the right way, then the process that leads one from Bp1,..., Bpn to Bq is a token of a reliable type of process – a type of process that is truth-conducive. This means that all or almost all tokens 5 For examples of beliefs formed on the basis of good reasons in the wrong way, see John Turri, "On the Relationship Between Propositional and Doxastic Justification," Philosophy and Phenomenological Research LXXX, 2 (2010): 312-326. Justification and the Uniqueness Thesis Again – A Response to Anantharaman 97 of that type will be such that, if the propositional contents of their input-states are true, then the propositional contents of their output-states are necessarily or most likely true. Second, a belief Bq is formed on the basis of Bp1,..., Bpn in the right way only when the truth of p1,..., pn is relevant to the truth of q. E.g., the process of forming a belief that √25 = 5 on the basis of the belief that It is raining in New York is a 100% reliable process, but the 'premise' here is irrelevant to the 'conclusion.' So a criterion of relevance must also be satisfied here. With these preliminary considerations in place, let me now address Anantharaman's criticism. Here I will concentrate only on the moderate permissiveness thesis. My arguments for the extreme version of the permissiveness thesis relied on the idea that we can rationally believe things on the basis of inconsistent reasons, and it is my understanding that I would need to deal with that issue in a more detailed manner first. The thesis that we can rationally believe things on the basis of inconsistent reasons deserves special attention itself. So this is not the place where I will try to make a case for it. Still, if I can successfully defend the moderate version of the permissiveness thesis against Anantharaman's criticism, my point will still hold that the uniqueness thesis is false. Anantharaman takes the concept of justification that I originally used to be a 'deontic' concept of justification, that is, as a concept that obeys to an 'ought implies can' principle. As it was pointed out above, I do indeed defend that ex ante justification or rationality is not only a matter of what evidence is available to the subject, but also of whether the subject is able to form the relevant doxastic attitude on the basis of her evidence in the right way. There is actually no 'ought implies can' principle involved here, however. Rather, what is involved is a 'can implies can' principle, where the former 'can' expresses epistemic permissibility and the latter one expresses cognitive ability. Even so, that concept of justification still seems to fit Anantharaman's bill. His point seems to be this: there is an alternative concept of rationality or justification, 'procedural rationality' or 'p–rationality', according to which only beliefs that were formed in an impeccable way count as justified. The uniqueness thesis – so we are told – would then be true when formulated with this concept of rationality. This is how Anantharaman explicates the notion of p–rationality: "We may say that an inference is p–rational if and only if no performance errors were made."6 What should count as a performance error here? Two types of error are pointed out by Anantharaman: first, you make a performance error in reasoning 6 Anantharaman, "Defending the Uniqueness Thesis," 133. Luis Rosa 98 about p when you reason in an invalid way about p;7 second, you make a performance error in reasoning about p when you fail to make a valid inference that bears on the truth of p.8 Now, when it comes to the ex post status of justification that pairs with the ex ante status that I mentioned above, the claim that S's belief is ex post justified or justifiably held is actually supposed to imply that S's belief is also 'procedurally rational', in the sense that it was produced through good reasoning. Believing that p is ex ante rational for S only when S has good reasons R to believe that p and S is able to competently form a belief toward p on the basis of R. Accordingly, S's belief that p is ex post justified (or S justifiably believes that p) only when S competently believes or holds the belief that p on the basis of good reasons R. So there is no invalid reasoning that confers ex post justification upon any belief: this type of performance error is excluded. My example in favor of the moderate permissiveness thesis (ergo, against the uniqueness thesis) was supposed to be one in which (i) the subject is ex post justified in believing a proposition p (i.e., she justifiably believes that p) on the basis of R, but (ii) she could be ex post justified in suspending judgment about p (i.e., she could justifiably suspend judgment about p) on the basis of R as well. But the fact that a subject is ex post justified in holding a certain doxastic attitude entails that the relevant attitude is ex ante justified for that subject. So if the example really satisfies the description I just gave, it is also an example in which (iii) one is ex ante justified in believing that p given one's reasons R, but (iv) one could also be ex ante justified in suspending judgment about p given one's reasons R. So let us look at the original example. I submit that no invalid reasoning is performed by the subject in the example – neither in the (actual) scenario of type (i), nor in the (counterfactual) scenario of type (ii). Consider the scenario of type (i) first. Here we have Amanda, in the actual world w1, performing a modus tollens type of inference from her reasons: (1) If I clicked the wrong link, my computer has a virus now, and (2) My computer has no virus now, to a belief in the conclusion: 7 In this context, we should understand the concepts of validity/invalidity in a broad sense, in such a way as to allow for inductive or probabilistic validity as well. 8 Anantharaman, "Defending the Uniqueness Thesis," 133. Justification and the Uniqueness Thesis Again – A Response to Anantharaman 99 (3) I did not click the wrong link. Amanda's inference is competent in w1, and her premises are justified. That should lead us to conclude that Amanda's belief is rationally held in w1, and that there is no invalid reasoning at all going on here. Now consider the scenario of type (ii), in a counterfactual situation w2. Here, Amanda has (1) and (2) available as reasons again – but now she lacks the competence to perform the relevant inference to the conclusion (3). She even considers whether (3) is the case. But as she cannot properly infer that (3) is true from (1) and (2), she cannot see why (3) must be true if (1) and (2) are. So she suspends judgment about (3). Again, there is no invalid reasoning going on here (in w2). There would be invalid reasoning if Amanda were to infer that (3) is false – but this is not the case in w2. It is not like Amanda is drawing a conclusion that does not follow from/is not made probable by her available reasons in w2. Notice also that Amanda's type of situation in w2 is not at all a far-fetched type of situation. Right now there are some complicated things that follow from what you and I believe (e.g., theorems of arithmetic) that we are not able to infer to be true in a competent manner. If we were to consider them, we would suspend judgment about them, and it would be rational for us to do so. But our suspension of judgment about such complicated truths would not constitute any use of invalid reasoning: we would not be reaching conclusions that do not follow from our reasons (we would not be reaching conclusions at all!). So the first type of performance error that was pointed out by Anantharaman – making an invalid inference – is avoided by Amanda in both the situation of type (i) (the w1 situation) and the situation of type (ii) (the w2 situation) of our example. That leaves us with what would be a second type of performance error, according to Anantharaman: failing to make a valid inference. The idea here seems to be that you are in a sense irrational when (a) you consider p, (b) there is a piece of good reasoning that could lead you from your reasons to a belief that p, but (c) you do not go through that piece of reasoning and you fail to competently form the belief that p. Let T again be a very complicated mathematical theorem, one that follows from certain basic axioms. Suppose you have that basic knowledge and you have all the concepts that are necessary to entertain T (they may be very simple ones). Suppose, further, that the shorter inferential path from those basic axioms to T is a very long and cunning path (although it is a finite path). Maybe only a very small percentage of humans could go through that path – or maybe even none! If certain theorem-proving algorithms could somehow be artificially implemented in your Luis Rosa 100 brain, or maybe if you were exposed to a certain type of intense mathematical training, then you would be able to derive T from your basic mathematical knowledge. But no such algorithm is actually implemented in your brain, and you have not been exposed to any such intense training. Now I ask you to consider T, and I ask you whether T is true or false. But you have no clue as to whether T is true or false, so you suspend judgment about T. Is your reasoning performance faulty in this case? Are you performing wrongly when you refrain from believing that T when you cannot see any reason to believe that T? Or: is it faulty to refrain from believing that T when you just cannot tell whether T is true? I submit that your reasoning performance is not faulty in this case. To be sure, you are failing to perform in a certain way – but that by itself is not sufficient in order to constitute a performance error. There is a sort of performance error in the vicinity, however: you are in error when you fail to perform a valid inference after considering its conclusion if, given your actual cognitive state, you could have performed that inference and reached that conclusion (but you suspended your judgment about that conclusion instead). Using the notions of possibleworlds semantics in order to interpret the modal term 'could' here, the qualification 'given your actual cognitive state' is supposed to put a constraint on the set of possible worlds that count as accessible from the actual one. The relevant relation of accessibility at play here – call it 'cognitive accessibility' – is such that a world v counts as accessible from a world w only when the reasoner's inferential abilities in v and in w are the same. But since we are assuming you could not have performed an inference from your basic mathematical knowledge to T in that sense, we cannot attribute to you that sort of performance error. The same applies to Amanda in the situation of type (ii) (the w2 situation). Amanda does not have the ability to perform a modus tollens type of inference – she is 'blind' to conclusions of inferences of that type. So failing to perform a valid inference constitutes a performance error only when there is a cognitively accessible situation (accessible from the actual one) in which the subject performs that inference. The cognitive resources available to Amanda in w2, however, will not allow her to perform the relevant modus tollens inference in any situation that is cognitively accessible to her. It would follow, then, that she does not make a performance error in w2. So she would also be 'procedurally rational' in w2. So, contrary to Anantharaman's suggestion, the example also shows that the uniqueness thesis is false even when it is formulated with a 'procedural' notion of rationality.