The general process view of learning, which guided research into learning for the first half of this century, has come under attack in recent years from several quarters. One form of criticism has come from proponents of the so-called biological boundaries approach to learning. These theorists have presented a variety of data showing that supposedly general laws of learning may in fact be limited in their applicability to different species and learning tasks, and they argue that the limitations are drawn (...) by the nature of each species' adaptation to the particular requirements of its natural environment. The biological boundaries approach has served an important critical function in the move away from general process learning theory, but it is limited in its ability to provide an alternative to the general process approach. In particular, the biological boundaries approach lacks generality, it is in some respects subservient to the general process tradition, and its ecological content is in too many cases limited toex post factoadaptive explanations of learning skills. A contrasting, ecological approach to learning, which can provide a true alternative to general process theory, is presented. The ecological approach begins by providing an ecological task description for naturally occurring instances of learning; this step answers the question:Whatdoes this animal learn to do? The next step is an analysis of the means by which learning occurs in the course of development, answering the question:Howdoes the animal learn to do this? On the basis of such analyses, local principles of adaptation are formulated to account for the learning abilities of individual species. More global principles are sought by generalization among these local principles and may form the basis for a general ecological theory of learning. (shrink)

Recent books by Paul Johnston, D. Z. Phillips, Philip Shields, and B. R. Tilghman all depict Wittgenstein as centrally concerned with ethics, but they range from representing his main works as expressing and advocating a particular religious-ethical outlook to arguing that his work has no ethical content but aims primarily to clarify such logical distinctions as that between ethical and empirical judgments. All four books raise the question about the moral philosopher's proper role, and each suggests a rather different answer. (...) Via the discussion of these books, I argue that Wittgenstein's stress on diversity in the ways of human life, his notion of conceptual grammar, the idea of a perspicuous representation, his lifelong involvement with art and his suggestions about its connection with morality, and his preoccupation with aspect-seeing-all suggest new possibilities of rehabilitating the historically recurrent idea that the philosopher may be a moral sage. (shrink)

Suppose that John asks, ‘Is the window open?’ and Mary replies, ‘The window is open.’ Then John and Mary have produced two distinct utterances, and in doing so, they have performed two different kinds of speech act. But clearly there is something that these utterances have in common. According to the standard theory of speech acts, in these utterances different illocutionary forces have been applied to the same propositional content. Similarly, if John and Mary both believe that roses are red, (...) the same propositional content is attributed to their individual mental states.The propositional contents of utterances and beliefs have traditionally been identified with propositions. In turn, propositions have been characterized as language-independent particulars that can be re-identified in different contexts. In this article, I will argue that various phenomena that have hitherto been explained by propositions are better understood in terms of propositional acts. (shrink)

In his 1987 book _Conditionals, Frank Jackson presents an argument to the effect that the indicative conditionals of natural language have the same truth conditions as the material conditional of truth-functional logic. This Jackson refers to as the "paradox of indicative conditionals." I offer a solution to this paradox by arguing that some conditionals that appear to be in the indicative mood are actually subjunctives, to which the paradox does not apply. I support this proposed solution with some historical observations (...) on the evolution of the English verb phrase. (edited). (shrink)

The article provides an example of the application of the techniques and results of historical linguistics to traditional problems in the philosophy of language. It takes as its starting point the dispute about the nature of facts that arose from the 1950 Aristotelian Society debate between J. L. Austin and P. F. Strawson. It is shown that, in some cases, expressions containing the noun fact refer to actions and events; while in other cases, such expressions do not have a referring (...) function at all. Thus, nothing corresponding to Strawson's 'pseudomaterial correlate' need be postulated in order to account for the reference of the noun fact. It is suggested that many philosophically problematic expressions may be better understood by tracing their historical evolution in natural language. (shrink)

The comparative method, closely identified with Darwinian evolutionary biology, also has a long pre-Darwinian history. The method derives its scientific power from its ability to interpret comparative observations with reference to a theory of relatedness among the entities being compared. Such scientifically powerful strong comparison is distinguished from weak comparison, which lacks such theoretical grounding. This paper examines the history of the strong comparison permitted by the comparative method from the early modern period to the threshold of the Darwinian revolution (...) in the mid nineteenth century. It interprets the work of early pioneers such as Belon, Willis, Perrault, and Tyson from this methodological perspective, rather than focusing on their particular anatomical findings. Although these early writers made formative scientific contributions through their comparative investigations, the more theoretically grounded application of the comparative method by Geoffroy, Cuvier, and Owen was instrumental in laying the foundation for its later incorporation into Darwinian evolutionary theory. (shrink)

An extensive literature overlapping economics, statistical decision theory and finance, contrasts expected utility [EU] with the more recent framework of mean–variance (MV). A basic proposition is that MV follows from EU under the assumption of quadratic utility. A less recognized proposition, first raised by Markowitz, is that MV is fully justified under EU, if and only if utility is quadratic. The existing proof of this proposition relies on an assumption from EU, described here as “Buridan’s axiom” after the French philosopher’s (...) fable of the ass that starved out of indifference between two bales of hay. To satisfy this axiom, MV must represent not only “pure” strategies, but also their probability mixtures, as points in the (σ, μ) plane. Markowitz and others have argued that probability mixtures are represented sufficiently by (σ, μ) only under quadratic utility, and hence that MV, interpreted as a mathematical re-expression of EU, implies quadratic utility. We prove a stronger form of this theorem, not involving or contradicting Buridan’s axiom, nor any more fundamental axiom of utility theory. (shrink)

A probability forecast scored ex post using a probability scoring rule (e.g. Brier) is analogous to a risky financial security. With only superficial adaptation, the same economic logic by which securities are valued ex ante – in particular, portfolio theory and the capital asset pricing model (CAPM) – applies to the valuation of probability forecasts. Each available forecast of a given event is valued relative to each other and to the “market” (all available forecasts). A forecast is seen to be (...) more valuable the higher its expected score and the lower the covariance of its score with the market aggregate score. Forecasts that score highly in trials when others do poorly are appreciated more than those with equal success in “easy” trials where most forecasts score well. The CAPM defines economically rational (equilibrium) forecast prices at which forecasters can trade shares in each other’s ex post score – or associated monetary payoff – thereby balancing forecast risk against return and ultimately forming optimally hedged portfolios. Hedging this way offers risk averse forecasters an “honest” alternative to the ruse of reporting conservative probability assessments. (shrink)