A necessity illusion for modal inferences from conditionals

Three experiments examined how people reason about what is possible or necessary when a conditional is true. Participants were asked to indicate whether it was necessary, possible or impossible for a specific instance to conform to one of the truth-table cases (pq, p¬q, ¬pq and ¬p¬q) (¬ = not), given the truth of the conditional. It was found that most participants, inconsistently, judged the pq case as necessary but the ¬pq or ¬p¬q cases as possible. Logically, these two kinds of judgments are contradictory. Moreover, a true conditional doesn’t imply that a specific instance under the conditional must be pq . Therefore, people demonstrate a necessity illusion for pq cases which contradicts their commitment to the possibility of ¬pq or ¬p¬q cases. Existing accounts of conditionals are unable to explain the contradiction and the necessity illusion. We propose an inference dissociation account and explore the theoretical implications of this necessity illusion.     

Positism: The Unexplored Solution to the Epistemic Regress Problem

As we trace a chain of reasoning backward, it must ultimately do one of four things: (i) end in an unjustified belief, (ii) continue infinitely, (iii) form a circle, or (iv) end in an immediately justified basic belief. This article defends positism—the view that, in certain circumstances, type‐(i) chains can justify us in holding their target beliefs. One of the assumptions that generates the epistemic regress problem is: (A) Person S is mediately justified in believing p iff (1) S has a doxastic reason q for p and (2) S is justified in believing q. Assumption (A) presupposes that reasoning is only justification transmitting, not justification generating. The article rejects (A) and argues that, in certain circumstances, reasoning itself is justification generating, even if that from which one is reasoning is not itself justified. It concludes by comparing positism with its infinitist, coherentist, and foundationalist rivals, acknowledging what is right about these other views.     

Matrix differential calculus with applications to simple,hadamard, and kronecker products

Several definitions are in use for the derivative of an m × p matrix function F(X) with respect to its n × q matrix argument X. We argue that only one of these definitions is a viable one, and that to study smooth maps from the space of n × q matrices to the space of m × p matrices it is often more convenient to study the map from nq-space to mp-space. Also, several procedures exist for a calculus of functions of matrices. It is argued that the procedure based on differentials is superior to other methods of differentiation, and leads inter alia to a satisfactory chain rule for matrix functions.     

On the Relationship between Propositional and Doxastic Justification

I argue against the orthodox view of the relationship between propositional and doxastic justification. The view under criticism is: if p is propositionally justified for S in virtue of S’s having reason(s) R, and S believes p on the basis of R, then S’s belief that p is doxastically justified. I then propose and evaluate alternative accounts of the relationship between propositional and doxastic justification, and conclude that we should explain propositional justification in terms of doxastic justification. If correct, this proposal would constitute a significant advance in our understanding of the sources of epistemic justification.     

Real knowledge

Philosophers have sought to characterize a type of knowledge — what I call real knowledge — which is significantly different from the ordinary concept of knowledge. The concept of knowledge as true, justified belief — what I call knowledge simpliciter — failed to depict the sought after real knowledge because the necessary and jointly sufficient conditions of knowledge simpliciter can be felicitously but accidentally fulfilled. Real knowledge is knowledge simpliciter plus a set of requirements which guarantee that the truth, belief and justification conditions are not accidentally conjoined. Two of those requirements have received considerable attention in recent literature by the defeasibility theorists and the causal theorists. I argue that a third requirement is needed to block the merely coincidental cosatisfaction of the belief and justification conditions and to capture our intuitions about the epistemic agent who possesses real knowledge. That condition ascribes a disposition to the real knower to believe all and only justified propositions in virtue of his/her belief that the propositions are justified. Two consequences of that requirement are discussed: (1) if S really knows that p, then S knows simpliciter that S knows simpliciter that p and (2) the iterative feature of real knowledge mentioned in (1) provides a basis for the rejection of a particularly pernicious form of scepticism.     

The Trouble with Infinitism

One way to solve the epistemic regress problem would be to show that we can acquire justification by means of an infinite regress. This is infinitism. This view has not been popular, but Peter Klein has developed a sophisticated version of infinitism according to which all justified beliefs depend upon an infinite regress of reasons. Klein's argument for infinitism is unpersuasive, but he successfully responds to the most compelling extant objections to the view. A key component of his position is his claim that an infinite regress is necessary, but not sufficient, for justified belief. This enables infinitism to avoid a number of otherwise compelling objections. However, it commits infinitism to the existence of an additional feature of reasons that is necessary and, together with the regress condition, sufficient for justified belief. The trouble with infinitism is that any such condition could account for the connection between justification and truth only by undermining the rationale for the regress condition itself.     

A Defense of Restricted Phenomenal Conservatism

Abstract

In this paper, I criticize Michael Huemer's phenomenal conservatism, the theory of justification according to which if it seems to S that p, then in the absence of defeaters, S thereby has at least some degree of justification for believing that p. Specifically, I argue that beliefs and hunches provide counterexamples to phenomenal conservatism. I then defend a version of restricted phenomenal conservatism, the view that some but not all appearances confer prima facie justification on their propositional contents. Specifically, I defend the view that S has defeasible justification for believing that p if and only if it seems to S that p and it seems to S that she is acquainted with the fact that makes p true. Finally, I criticize Huemer's self-defeat argument for phenomenal conservatism.     

Epistemic justification and premise acceptability

In this paper, we want to explore the connection between premises' being acceptable and their being in some sense justified. The equivalence of premise acceptability and justification seems intuitively correct. But to argue for such a connection, we need to analyze the concepts of acceptability and justification. Such an analysis also seems necessary if this equivalence is to advance our understanding of premise acceptability. Following L. J. Cohen, we may say S believes that p when S is disposed to feel it true that p, while S accepts that p when S takes that p as a premise for further deliberation or action. Reasons for belief are reasons for acceptance, and epistemological (as opposed to pragmatic) reasons for acceptance are reason for belief. Following William P. Alston, we may explicate being a justifying reason for belief through the notion of an adequate ground on which the belief is based. In turn, adequacy of ground means that the mechanism grounding the belief is reliable. Given these notions, we may define a concept of justification in terms of presumptive adequacy.     

A Logical Transmission Principle for Conclusive Reasons

Dretske's conclusive reasons account of knowledge is designed to explain how epistemic closure can fail when the evidence for a belief does not transmit to some of that belief's logical consequences. Critics of Dretske dispute the argument against closure while joining Dretske in writing off transmission. This paper shows that, in the most widely accepted system for counterfactual logic (David Lewis's system VC), conclusive reasons are governed by an informative, non-trivial, logical transmission principle. If r is a conclusive reason for believing p in Dretske's sense, and if p logically implies q, and if p and q satisfy one additional condition, it follows that r is a conclusive reason for believing q. After introducing this additional condition, I explain its intuitive import and use the condition to shed new light on Dretske's response to scepticism, as well as on his distinction between the so-called ‘lightweight’ and ‘heavyweight’ implications of a piece of perceptual knowledge.     

Scepticism,defeasible evidence and entitlement

The paper starts by describing and clarifying what Williamson calls the consequence fallacy. I show two ways in which one might commit the fallacy. The first, which is rather trivial, involves overlooking background information; the second way, which is the more philosophically interesting, involves overlooking prior probabilities. In the following section, I describe a powerful form of sceptical argument, which is the main topic of the paper, elaborating on previous work by Huemer. The argument attempts to show the impossibility of defeasible justification, justification based on evidence which does not entail the (allegedly) justified proposition or belief. I then discuss the relation between the consequence fallacy, or some similar enough reasoning, and that form of argument. I argue that one can resist that form of sceptical argument if one gives up the idea that a belief cannot be justified unless it is supported by the totality of the evidence available to the subject—a principle entailed by many prominent epistemological views, most clearly by epistemological evidentialism. The justification, in the relevant cases, should instead derive solely from the prior probability of the proposition. A justification of this sort, that does not rely on evidence, would amount to a form of entitlement, in (something like) Crispin Wright’s sense. I conclude with some discussion of how to understand prior probabilities, and how to develop the notion of entitlement in an externalist epistemological framework.     

KEEPING TRACK OF THE GETTIER PROBLEM

This paper argues that for someone to know proposition p inferentially it is not enough that his belief in p and his justification for believing p covary with the truth of p through a sphere of possibilities. A further condition on inferential knowledge is that p's truth‐maker is identical with, or causally related to, the state of affairs the justification is grounded in. This position is dubbed ‘identificationism.’     

Knowledge attribution revisited: a deflationary account

According to the usual way of understanding how true knowledge attribution works, it is not right to attribute knowledge of p to S unless p is true and S is justified in believing p. This assumption seems to hold even if we shun away from the idea that we can give an analysis of knowledge in terms of necessary and sufficient conditions. I want to raise some suspicions on the correctness of this traditional picture. I suggest that justification is not always perceived as a necessary condition for true knowledge attribution, according to our pre-theoretical usage of standard epistemic terms. This is not to say that justification is never seen as an important requirement; sometimes it certainly is. Still, the full-fledged, traditional position on epistemic justification needs to be seriously qualified. Ultimately, I will contend that this result lends support to a rival epistemological standpoint — what we might dub a Moderate Peircean stance on epistemic matters.     

Schaffer's Demon

Jonathan Schaffer (2010) has summoned a new sort of demon – which he calls the debasing demon – that apparently threatens all of our purported knowledge. We show that any debasing skeptical argument must attack the justification condition and can do so only if a plausible thesis about justification is false.     

Evidential Preemption

As a general rule, whenever a hearer is justified in forming the belief that p on the basis of a speaker’s testimony, she will also be justified in assuming that the speaker has formed her belief appropriately in light of a relevantly large and representative sample of the evidence that bears on p. In simpler terms, a justification for taking someone’s testimony entails a justification for trusting her assessment of the evidence. This introduces the possibility of what I will call “evidential preemption.” Evidential preemption occurs when a speaker, in addition to offering testimony that p, also warns the hearer of the likelihood that she will subsequently be confronted with apparently contrary evidence: this is done, however, not so as to encourage the hearer to temper her confidence in p in anticipation of that evidence, but rather to suggest that the (apparently) contrary evidence is in fact misleading evidence or evidence that has already been taken into account. Either way, the speaker is signalling to the hearer that the subsequent disclosure of this evidence will not require her to significantly revise her belief that p. Such preemption can effectively inoculate an audience against future contrary evidence, and thereby creates an opening for a form of exploitative manipulation that I will call “epistemic grooming.” Nonetheless, I argue, not all uses of evidential preemption are nefarious; it can also serve as an important tool for guiding epistemically limited agents though complex evidential scenarios.     

The effect of justified video game violence on aggressive behavior and moderated immersion: An experimental approach

The effect of violent video games on aggressive behavior is an important topic in the field of game research. Recently, growing evidence suggests that justified game violence decreases feelings of guilt caused by in-game immoral behavior. However, little is known about the impact on aggressive behavior, and whether other factors moderate this effect. In a two-factor experiment, we tested the impact of justification of video game violence on aggressive behavior, and whether this effect would be enhanced by game immersion. Pilot experiment 1 (N = 60) and pilot experiment 2 (N = 40) demonstrated that the justification of violence and game immersion was successfully controlled by avatar and graphics quality. In the Main experiment, 123 participants played one of four conditions of a video game (2 [justification: justified vs. unjustified violence] × 2 [immersion: high vs. low immersion]) and it was found that participants who played in the justified violence condition reported greater aggressive behavior than those in the unjustified violence condition. In addition, participants who played in high immersion reported greater aggressive behavior than those in low immersion. However, game immersion did not moderate the effects of justified violence. This unexpected effect is likely due to participants' distancing themselves from and identifying less with their violent avatars.     

Does Doxastic Justification Have a Basing Requirement?

The distinction between propositional and doxastic justification is the distinction between having justification to believe that P (= propositional justification) versus having a justified belief in P (= doxastic justification). The focus of this paper is on doxastic justification and on what conditions are necessary for having it. In particular, I challenge the basing demand on doxastic justification, i.e. the idea that one can have a doxastically justified belief only if one's belief is based on an epistemically appropriate reason. This demand has been used to refute versions of coherentism and conservatism about perceptual justification, as well as to defend phenomenal ‘conservatism’ and other views besides. In what follows, I argue that there is virtually no reason to think there is a basing demand on doxastic justification. I also argue that, even if the basing demand were true, it would still fail to serve the dialectical purposes for which it has been employed in arguments concerning coherentism, conservatism, and phenomenal ‘conservatism’. I conclude by discussing the fact that knowledge has a basing demand and I show why this needn't raise the same sort of problems for coherentism and conservatism that doxastic justification's basing demand seemed to raise.     

Skepticism about Skepticism about Moral Responsibility

This article rejects Gideon Rosen's skeptical argument that attributions of blameworthiness are never epistemically justified. Granting Rosen's controversial claim that an act is blameworthy only if it is either akratic or the causal upshot of some akratic act, I show that we can and should resist his skeptical conclusion. I show, first, that Rosen's argument is, at best, hostage to a much more global skepticism about attributions of praiseworthiness, doxastic justification, and other phenomena which essentially involve causal‐historical facts about mental states. I then show how, equipped with proper background knowledge, we can justifiedly attribute blameworthiness.     

Appearances,Rationality, and Justified Belief

One might think that its seeming to you that p makes you justified in believing that p. After all, when you have no defeating beliefs, it would be irrational to have it seem to you that p but not believe it. That view is plausible for perceptual justification, problematic in the case of memory, and clearly wrong for inferential justification. I propose a view of rationality and justified belief that deals happily with inference and memory. Appearances are to be evaluated as ‘sound’ or ‘unsound.’ Only a sound appearance can give rise to a justified belief, yet even an unsound appearance can ‘rationally require’ the subject to form the belief. Some of our intuitions mistake that rational requirement for the belief’s being justified. The resulting picture makes it plausible that there are also unsound perceptual appearances. I suggest that to have a sound perceptually basic appearance that p, one must see that p.