The 'Evolution of Cooperation' addresses a simple yet age-old question; If living things evolve through competition, how can cooperation ever emerge? Despite the abundant evidence of cooperation all around us, there existed no purely naturalistic answer to this question until 1979, when Robert Axelrod famously ran a computer tournament featuring a standard game-theory exercise called The Prisoner's Dilemma. To everyone's surprise, the program that won the tournament, named Tit for Tat, was not only the simplest but the most "cooperative" entrant. (...) This unexpected victory proved that cooperation - one might even say altruism - is mathematically possible and therefore needs no hidden hand or divine agent to create and sustain it. A great roadblock to the understanding of all sorts of behavior was at last removed. The updated edition includes an extensive new chapter on cooperation in cancer cells and among terrorist organizations. (shrink)

This paper begins by raising a puzzle about what function our use of the word ‘rational’ could serve. To solve the puzzle, I introduce a view I call Epistemic Communism: we use epistemic evaluations to promote coordination among our basic belief-forming rules, and the function of this is to make the acquisition of knowledge by testimony more efficient.

Paul Faulkner presents a new theory of testimony - the basis of much of what we know. He addresses the questions of what makes it reasonable to accept a piece of testimony, and what warrants belief formed on that basis. He rejects rival theories and argues that testimonial knowledge and testimonially warranted belief are based on trust.

Short abstract (98 words). Reasoning is generally seen as a means to improve knowledge and make better decisions. However, much evidence shows that reasoning often leads to epistemic distortions and poor decisions. This suggests that the function of reasoning should be rethought. Our hypothesis is that the function of reasoning is argumentative. It is to devise and evaluate arguments intended to persuade. Reasoning so conceived is adaptive given humans’ exceptional dependence on communication and vulnerability to misinformation. A wide range of (...) evidence in the psychology of reasoning and decision making can be reinterpreted and better explained in the light of this hypothesis. (shrink)

Psychologists have emphasized children's acquisition of information through firsthand observation. However, many beliefs are acquired from others' testimony. In two experiments, most 4yearolds displayed sceptical trust in testimony. Having heard informants' accurate or inaccurate testimony, they anticipated that informants would continue to display such differential accuracy and they trusted the hitherto reliable informant. Yet they ignored the testimony of the reliable informant if it conflicted with what they themselves had seen. By contrast, threeyearolds were less selective in trusting a reliable (...) informant. Thus, young children check testimony against their own experience and increasingly recognise that some informants are more trustworthy than others. (shrink)

Humans massively depend on communication with others, but this leaves them open to the risk of being accidentally or intentionally misinformed. To ensure that, despite this risk, communication remains advantageous, humans have, we claim, a suite of cognitive mechanisms for epistemic vigilance. Here we outline this claim and consider some of the ways in which epistemic vigilance works in mental and social life by surveying issues, research and theories in different domains of philosophy, linguistics, cognitive psychology and the social sciences.

Our trust in the word of others is often dismissed as unworthy, because the illusory ideal of "autonomous knowledge" has prevailed in the debate about the nature of knowledge. Yet we are profoundly dependent on others for a vast amount of what any of us claim to know. Coady explores the nature of testimony in order to show how it might be justified as a source of knowledge, and uses the insights that he has developed to challenge certain widespread assumptions (...) in the areas of history, law, mathematics, and psychology. (shrink)

When is a testimony-based belief justified? According to so-called "Anti-Reductionism," the principle that a hearer is prima facie justified to take what another tells them at face value is true. I call this position "Liberal Foundationalism." I call it "liberal" for it is more liberal than "Moderate Foundationalism" that holds that perception-based beliefs are prima facie justified but testimony-based beliefs are not. Liberal Foundationalism has two interpretations: the principle is a contingent empirical truth, or an a priori necessary truth. I (...) call the view that the principle is a priori necessary "Liberal Fundamentalism." This chapter defends Liberal Fundamentalism against objections in the first half, and then in the second half it introduces "Weak Liberal Fundamentalism," the view that it is a priori necessary that testimony provides some epistemic support, but perhaps not enough, absent defeat, for knowledge. In later work I abandon the view that the principle is a priori necessary, but I still maintain the distinction between Strong and Weak variants of the principle, and the replies to many of the objections to the principle. (shrink)

Sinan Dogramaci has recently developed a view according to which the function of epistemic evaluations—like calling someone’s behavior “rational” or “irrational”—is to encourage or discourage the behavior evaluated. This view promises to explain the rational authority of testimony, by describing a social practice that promotes the coordination of epistemic procedures across a community. We argue that Dogramaci’s view is unsatisfactory, for two reasons. First, the social practice at its heart is vulnerable to free riders. Second, even if the problem of (...) free riders can be solved, it “alienates” epistemic agents from the testimony that they receive, in that, though they will accept testimony from their fellows, they will have no reason to do so. We argue that a more satisfactory view can be had if we couple the genuine insights that are to be found in Dogramaci’s proposal with the recognition that testimony is an excludible good that is often distributed according to market forces. It is this fact about test.. (shrink)

Coady’s book is probably the single most comprehensive treatment of philosophical questions relating to testimony and as such must be read by anyone interested in the topic. His epistemological conclusions concerning testimony challenge much of the philosophical tradition.

The assumption that we largely lack reasons for accepting testimony has dominated its epistemology. Given the further assumption that whatever reasons we do have are insufficient to justify our testimonial beliefs, many conclude that any account of testimonial knowledge must allow credulity to be justified. In this paper I argue that both of these assumptions are false. Our responses to testimony are guided by our background beliefs as to the testimony as a type, the testimonial situation, the testifier's character and (...) the truth of the proposition testified to. These beliefs provide reasons for our responses. Thus, we usually do have reasons, in the sense of propositions believed, for accepting testimony and these reasons can provide evidence for the testimonial beliefs we form. (shrink)

By systematically biasing our beliefs, self-deception can endanger our ability to successfully convey our messages. It can also lead lies to degenerate into more severe damages in relationships. Accordingly, I suggest that the biases reviewed in the target article do not aim at self-deception but instead are the by-products of several other mechanisms: our natural tendency to self-enhance, the confirmation bias inherent in reasoning, and the lack of access to our unconscious minds.