What is the function of cognition? On one influential account, cognition evolved to co-ordinate behaviour with environmental change or complexity. Liberal interpretations of this view ascribe cognition to an extraordinarily broad set of biological systems—even bacteria, which modulate their activity in response to salient external cues, would seem to qualify as cognitive agents. However, equating cognition with adaptive flexibility per se glosses over important distinctions in the way biological organisms deal with environmental complexity. Drawing on contemporary advances in theoretical biology (...) and computational neuroscience, we cash these distinctions out in terms of different kinds of generative models, and the representational and uncertainty-resolving capacities they afford. This analysis leads us to propose a formal criterion for delineating cognition from other, more pervasive forms of adaptive plasticity. On this view, biological cognition is rooted in a particular kind of functional organisation; namely, that which enables the agent to detach from the present and engage in counterfactual inference. (shrink)

Between inventing the concept of a universal computer in 1936 and breaking the German Enigma code during World War II, Alan Turing, the British founder of computer science and artificial intelligence, came to Princeton University to study mathematical logic. Some of the greatest logicians in the world--including Alonzo Church, Kurt Gödel, John von Neumann, and Stephen Kleene--were at Princeton in the 1930s, and they were working on ideas that would lay the groundwork for what would become known as computer science. (...) Though less well known than his other work, Turing's 1938 Princeton PhD thesis, "Systems of Logic Based on Ordinals," which includes his notion of an oracle machine, has had a lasting influence on computer science and mathematics. This book presents a facsimile of the original typescript of the thesis along with essays by Andrew Appel and Solomon Feferman that explain its still-unfolding significance. A work of philosophy as well as mathematics, Turing's thesis envisions a practical goal--a logical system to formalize mathematical proofs so they can be checked mechanically. If every step of a theorem could be verified mechanically, the burden on intuition would be limited to the axioms. Turing's point, as Appel writes, is that "mathematical reasoning can be done, and should be done, in mechanizable formal logic." Turing's vision of "constructive systems of logic for practical use" has become reality: in the twenty-first century, automated "formal methods" are now routine. Presented here in its original form, this fascinating thesis is one of the key documents in the history of mathematics and computer science. (shrink)

This paper defends a key aspect of the Peircean conception of truth—the idea that truth is in some sense epistemically-constrained. It does so by exploring parallels between Peirce’s epistemology of inquiry and that of Wittgenstein in On Certainty. The central argument defends a Peircean claim about truth by appeal to a view shared by Peirce and Wittgenstein about the structure of reasons. This view relies on the idea that certain claims have a special epistemic status, or function as what are (...) popularly called ‘hinge propositions’. (shrink)

Circumscribed delusional beliefs can follow brain injury. We suggest that these involve anomalous perceptual experiences created by a deficit to the person's perceptual system, and misinterpretation of these experiences due to biased reasoning. We use the Capgras delusion (the claim that one or more of one's close relatives has been replaced by an exact replica or impostor) to illustrate this argument. Our account maintains that people voicing this delusion suffer an impairment that leads to faces being perceived as drained of (...) their normal affective significance, and an additional reasoning bias that leads them to put greater weight on forming beliefs that are observationally adequate rather than beliefs that are a conservative extension of their existing stock. We show how this position can integrate issues involved in the philosophy and psychology of belief, and examine the scope for mutually beneficial interaction. (shrink)

There is wide agreement that the derivation and use of human embryonic stem cells from embryos remaining after infertility treatment morally require the informed consent of the IVF patients who undertook the treatment. However, there continues to be controversy over whether hESC research involving leftover embryos created with eggs or sperm from third-party donors requires the consent of these donors. In the United States, the lack of consensus on this issue manifests itself in a conflict between two entities that play (...) an important role in hESC research policy: the National Institutes of Health, which federally funds the research, and the National Academy of Sciences, which has produced.. (shrink)

Majority-Minority electoral districts, while increasing the number of minorities in legislatures, work to deepen divisions among racial groups, to exacerbate the systematic disadvantages of some individuals, and to impede effective representation. I examine another form of race-conscious districting that will increase marginalized minority presence in legislatures while avoiding these problems.

Pietraszewski exemplifies the need for computational theory using group conflict; I complement this with an example of group cooperation. He criticizes past theories for having black boxes; I suggest his theory also has a black box – the concept of costs. He divides what mentally constitutes a group from mere ancillary attributes; I hazard that some of these attributes are essential.

This study focuses on concepts and, ultimately, their possible implementation in brains. Especially salient is analysis of Jerry Fodor's work. The view of concepts found therein is one where many of both are "simple": to be ascribed or to token most concepts doesn't require being ascribed or tokening any other concepts, and most symbols lack "parts" which are themselves symbols. This is, I think, a very popular, and mistaken, view. ;In chapter 1, I argue that Fodor's theory of content is, (...) contra its goals, neither naturalistic nor atomistic. A deep mistake undermines both, viz. that there's no way to individuate a mental symbol non-semantically. This leads to chapter 2, where I explore the much neglected notion of Mentalese syntax. I argue that there are three possible principles of syntactic type individuation, and that these turn out not only to be incompatible but also inadequate for a "language of thought." I conclude that the idea of simple mental symbols is in trouble. ;This then allows me to argue in chapter 3 that we don't have to fear intentional holism , which sanctions the prevalence of complex concepts. I next sketch, in chapter 4, the sort of complex symbols needed to implement complex concepts. The chapter's bulk consists in an empirical argument for the complexity view via seven domains of current cognitive science, including concept context dependency, typicality effects, association, and reasoning. ;Chapter 5 concludes by exploring connectionism. I argue that, despite problems, connectionism seems on the right track in a way that Fodor's computationalism isn't. For example, it's more explicitly brain-like; in dropping the idea of mental computation over symbols it's free from the syntax problems of chapter 2; and, most important, it's highly compatible with the complexity view, which best characterized the cognitive processes of chapter 4. (shrink)

In this pivotal year for gene editing, the breakthrough molecular system CRISPR–Cas9 has advanced on three fronts. In under seven months, an influential scientific body—the National Academies of Sciences, Engineering, and Medicine the National Academies of Sciences, Engineering, and Medicine—cracked open the door to human germline gene editing, ownership of patents covering CRISPR–Cas9 came into much sharper focus as a result of a dispute between two parties, and experiments showing proof of concept of the most controversial of uses—altering germlines of (...) humans—were revealed as having been successfully performed by a mainstream laboratory. Given the vast spoils that await the patent owners, final results of all patent disputes over CRISPR–Cas9 patents may stretch on for years. Meanwhile, bioethical considerations of CRISPR–Cas9 have also been contentious as the United States and other countries grapple with how best to regulate gene editing. (shrink)