The independence of irrelevant alternatives is a popular and important axiom of decision theory. It states, roughly, that one’s choice from a set of options should not be influenced by the addition or removal of further, unchosen options. In recent debates, a number of authors have given putative counterexamples to it, involving intuitively rational agents who violate IIA. Generally speaking, however, these counterexamples do not tend to move IIA’s proponents. Their strategy tends to be to individuate the options that the (...) agent faces differently, so that the case no longer counts as a violation of IIA. In this paper, we examine whether this strategy succeeds. We argue that the ways of individuating options required to save IIA from the most problematic counterexamples—in particular, cases where agents violate IIA due to nonconsequentialist moral beliefs—do so only at the expense of severely compromising its central function within decision theory. (shrink)

Many economists and philosophers assume that status quo bias is necessarily irrational. I argue that, in some cases, status quo bias is fully rational. I discuss the rationality of status quo bias on both subjective and objective theories of the rationality of preferences. I argue that subjective theories cannot plausibly condemn this bias as irrational. I then discuss one kind of objective theory, which holds that a conservative bias toward existing things of value is rational. This account can fruitfully explain (...) some compelling aspects of common sense morality, and it may justify status quo bias. (shrink)

Suppose that you are trying to pursue a morally worthy goal, but cannot do so without incurring some moral costs. At the outset, you believed that achieving your goal was worth no more than a given moral cost. And suppose that, time having passed, you have wrought only harm and injustice, without advancing your cause. You can now reflect on whether to continue. Your goal is within reach. What's more, you believe you can achieve it by incurring—from this point forward—no (...) more cost than it warranted at the outset. If you now succeed, the total cost will exceed the upper bound marked at the beginning. But the additional cost from this point is below that upper bound. And the good you will achieve is undiminished. How do the moral costs you have already inflicted bear upon your decision now? (shrink)

The practice of giving the wealthy perpetual control of their assets is re-emerging in an era of great wealth inequality, long after it had been banned in common law countries. The philosophical justification for such control rests on the claim that there are posthumous rights to wealth, and that such rights do not extend in problematic way to other goods, such as political suffrage. On the basis of such a claim, we give people freedom of testation, and deem them vulnerable (...) to posthumous harm. I present a short history of legally sanctioned posthumous control of property in common law, and I argue that its philosophical justification is untenable. No principled case for posthumous rights to wealth survives scrutiny, and the large and powerful institutions that enforce such rights are morally illegitimate. (shrink)

I review proposed skepticisms in recent literature (or skeptical invariantisms, if we understand skepticism semantically), contrast their basic commitments and highlight some of their comparative theoretical attractions and problems. To help set the scene for the discussion, I start with Unger’s (1975) modern classic of global skepticism about knowledge (and justification). I then distinguish three extant categories of skepticism in the recent literature: two non‐traditional and one more traditional. On the non‐traditional side are fallibilist science‐based skepticism (which relaxes thestringencyof the (...) standard of knowledge) and practical skepticism (which questions theintellectualcharacter of the standard of knowledge) and on the traditional side high‐standard/infallibilist. I then briefly present and discuss representatives of each category. (shrink)

I review proposed skepticisms in recent literature (or skeptical invariantisms, if we understand skepticism semantically), contrast their basic commitments and highlight some of their comparative theoretical attractions and problems. To help set the scene for the discussion, I start with Unger’s (1975) modern classic of global skepticism about knowledge (and justification). I then distinguish three extant categories of skepticism in the recent literature: two non‐traditional and one more traditional. On the non‐traditional side are fallibilist science‐based skepticism (which relaxes the stringency (...) of the standard of knowledge) and practical skepticism (which questions the intellectual character of the standard of knowledge) and on the traditional side high‐standard/infallibilist. I then briefly present and discuss representatives of each category. (shrink)

Wilfrid Sellars [1962: 1] described philosophy as an attempt to ‘understand how things in the broadest possible sense of the term hang together in the broadest possible sense of the term’. But it is distinctive of philosophy that many of us are interested not only in how the world is but in ways that it could be. That is, philosophy is concerned with facts about modality. Some of the most important arguments in philosophy hinge on modal premises, and philosophers have (...) typically assumed special expertise in evaluating these modal premises. Replicating Goldvarg and Johnson-Laird’s [2000] study of modal illusions, we show that training in mathematics and not philosophy predicts success in overcoming such illusions (n = 395). This study is the first to test the modal expertise of professional philosophers directly. Our findings undermine claims to modal expertise. Philosophical training does not inoculate expert philosophers against basic mistakes in modal judgment. (shrink)

The verb ‘to know’ can be used both in ascriptions of propositional knowledge and ascriptions of knowledge of acquaintance. In the formal epistemology literature, the former use of ‘know’ has attracted considerable attention, while the latter is typically regarded as derivative. This attitude may be unsatisfactory for those philosophers who, like Russell, are not willing to think of knowledge of acquaintance as a subsidiary or dependent kind of knowledge. In this paper we outline a logic of knowledge of acquaintance in (...) which ascriptions like ‘Mary knows Smith’ are regarded as formally interesting in their own right, remaining neutral on their relation to ascriptions of propositional knowledge. The resulting logical framework, which is based on Hintikka’s modal approach to epistemic logic, provides a fresh perspective on various issues and notions at play in the philosophical debate on acquaintance. (shrink)

Humans typically display hindsight bias. They are more confident that the evidence available beforehand made some outcome probable when they know the outcome occurred than when they don't. There is broad consensus that hindsight bias is irrational, but this consensus is wrong. Hindsight bias is generally rationally permissible and sometimes rationally required. The fact that a given outcome occurred provides both evidence about what the total evidence available ex ante was, and also evidence about what that evidence supports. Even if (...) you in fact evaluate the ex ante evidence correctly, you should not be certain of this. Then, learning the outcome provides evidence that if you erred, you are more likely to have erred low rather than high in estimating the degree to which the ex ante evidence supported the hypothesis that that outcome would occur. (shrink)

We know that Homo sapiens will not exist forever. Given this, how should our species end? What are the reasons, if any, to delay our extinction? In this paper, I show that the pre-eminent reasons which favour prolonging the existence of the species are partial: they will arise from the particular attachments and projects of the final few generations. While there may also be impartial reasons to prolong the species, these reasons are liable, with time, to reverse their valence: we (...) can be reasonably confident that they will ultimately recommend hastening the demise of the species. Consequently, it is likely that our descendants will eventually face a difficult -- possibly tragic -- conflict, between partial duties that recommend living on, and an impartial duty to extinguish the species. (shrink)

Do people tend to be overconfident? Many think so. They’ve run studies on whether people are calibrated: whether their average confidence in their opinions matches the proportion of those opinions that are true. Under certain conditions, people are systematically ‘over-calibrated’—for example, of the opinions they’re 80% confident in, only 60% are true. From this empirical over-calibration, it’s inferred that people are irrationally overconfident. My question: When and why is this inference warranted? Answering it requires articulating a general connection between being (...) rational and being right—something extant studies have not done. I show how to do so using the notion of deference. This provides a theoretical foundation for calibration research, but also reveals a flaw: the connection between being rational and being right is much weaker than is standardly assumed, since rational people can often be expected to be miscalibrated. Thus we can’t test whether people are overconfident by simply testing whether they are over-calibrated; instead, we must try to predict the rational deviations from calibration, and then compare those predictions to people’s performance. I show how this can be done—and that doing so complicates the interpretation of robust empirical effects. (shrink)

This paper is about guessing: how people respond to a question when they aren’t certain of the answer. Guesses show surprising and systematic patterns that the most obvious theories don’t explain. We argue that these patterns reveal that people aim to optimize a tradeoff between accuracy and informativity when forming their guess. After spelling out our theory, we use it to argue that guessing plays a central role in our cognitive lives. In particular, our account of guessing yields new theories (...) of belief, assertion, and the conjunction fallacy—the psychological finding that people sometimes rank a conjunction as more probable than one of its conjuncts. More generally, we suggest that guessing helps explain how boundedly rational agents like us navigate a complex, uncertain world. (shrink)

Business and Economic textbooks warn against committing the Sunk Cost Fallacy: you, rationally, shouldn't let unrecoverable costs influence your current decisions. In this paper, I argue that this isn't, in general, correct. Sometimes it's perfectly reasonable to wish to carry on with a project because of the resources you've already sunk into it. The reason? Given that we're social creatures, it's not unreasonable to care about wanting to act in such a way so that a plausible story can be told (...) about you according to which your diachronic behavior doesn't reveal that you've suffered, what I will call, diachronic misfortune. Acting so as to hide that you've suffered diachronic misfortune involves striving to make yourself easily understood while disguising any shortcomings that might damage your reputation as a desirable teammate. And making yourself easily understood to others while hiding your flaws will, sometimes, put pressure on you to honor sunk costs. (shrink)

It is sometimes said that faith is recalcitrant in the face of new evidence, but it is puzzling how such recalcitrance could be rational or laudable. I explain this aspect of faith and why faith is not only rational, but in addition serves an important purpose in human life. Because faith requires maintaining a commitment to act on the claim one has faith in, even in the face of counter-evidence, faith allows us to carry out long-term, risky projects that we (...) might otherwise abandon. Thus, faith allows us to maintain integrity over time. (shrink)

Recent findings from psychology and behavioral economics suggest that we are “predictably irrational” in the pursuit of our interests. Paternalists from both the social sciences and philosophy use these findings to defend interfering with people's consumption choices for their own good. We should tax soda, ban cigarettes, and mandate retirement savings to make people healthier and wealthier than they’d be on their own. Our thesis is that the standard arguments offered in support of restricting people’s consumption choices for their own (...) good also imply support for “epistocratic” restrictions on people’s voting choices for their own good. Indeed, the philosophical case for paternalistic restrictions on voting choices may be stronger than the case for restricting personal consumption choices. So, paternalists face a dilemma: either endorse less interference with consumption choices or more interference with voting choices. (shrink)

The gambler’s fallacy is the tendency to expect random processes to switch more often than they actually do—for example, to think that after a string of tails, a heads is more likely. It’s often taken to be evidence for irrationality. It isn’t. Rather, it’s to be expected from a group of Bayesians who begin with causal uncertainty, and then observe unbiased data from an (in fact) statistically independent process. Although they converge toward the truth, they do so in an asymmetric (...) way—ruling out “streaky” hypotheses more quickly than “switchy” ones. As a result, the majority (and the average) exhibit the gambler’s fallacy. If they have limited memory, this tendency persists even with arbitrarily-large amounts of data. Indeed, such Bayesians exhibit a variety of the empirical trends found in studies of the gambler’s fallacy: they expect switches after short streaks but continuations after long ones; these nonlinear expectations vary with their familiarity with the causal system; their predictions depend on the sequence they’ve just seen; they produce sequences that are too switchy; and they exhibit greater rates of gambler’s reasoning when forming binary predictions than when forming probability estimates. In short: what’s been thought to be evidence for irrationality may instead be rational responses to limited data and memory. (shrink)

Argues from the rationality of nostalgia, affirmation, and regret to a principle of ‘specificity’: it can be rational to respond more strongly to facts that provide us with reasons than to the fact that such reasons exist.