Traditionally a scientific theory is viewed as based on universal laws of nature that serve as axioms for logical deduction. In analyzing the logical structure of evolutionary biology, Elisabeth Lloyd argues that the semantic account is more appropriate and powerful. This book will be of interest to biologists and philosophers alike.

1. When we attribute beliefs, desires, and other states of common sense psychology to a person, or for that matter to an animal or an artifact, we are assuming or presupposing that the person or object can be treated as an intentional system. 2. An intentional system is one which is rational through and through; its beliefs are those it ought to have, given its perceptual capacities, its epistemic needs, and its biography…. Its desires are those it ought to have, (...) given its biological needs and the most practicable means of satisfying them…. And its behavior will consist of those acts that it would be rational for an agent with those beliefs and desires to perform. [beliefs + desires  action] 3. If rationality is absent, we cannot coherently ascribe beliefs at all. 4. Therefore, no experiment could demonstrate that people systematically invoke invalid or irrational inferential strategies. (shrink)

The old quantum theory of black body radiation was manifestly logically inconsistent. It required the energies of electric resonators to be both quantized and continuous. To show that this manifest inconsistency was inessential to the theory's recovery of the Planck distribution law, I extract a subtheory free of this manifest inconsistency but from which Planck's law still follows.

There are several conceptions of truth, such as the classical correspondence conception, the coherence conception and the pragmatic conception. The classical correspondence conception, or Aristotelian conception, received a mathematical treatment in the hands of Tarski (cf. Tarski [1935] and [1944]), which was the starting point of a great progress in logic and in mathematics. In effect, Tarski's semantic ideas, especially his semantic characterization of truth, have exerted a major influence on various disciplines, besides logic and mathematics; for instance, linguistics, the (...) philosophy of science, and the theory of knowledge. The importance of the Tarskian investigations derives, among other things, from the fact that they constitute a mathematical, formal mark to serve as a reference for the philosophical (informal) conceptions of truth. Today the philosopher knows that the classical conception can be developed and that it is free from paradoxes and other difficulties, if certain precautions are taken. We believe that is not an exaggeration if we assert that Tarski's theory should be considered as one of the greatest accomplishments of logic and mathematics of our time, an accomplishment which is also of extraordinary relevance to philosophy, as we have already remarked. In this paper we show that the pragmatic conception of truth, at least in one of its possible interpretations, has also a mathematical formulation, similar in spirit to that given by Tarski to the classical correspondence conception. (shrink)

For three centuries, philosophers have mounted defenses against the melan genie with an obsessive intensity comparable to the Reaganite determination to squander American wealth on defenses against a Communist threat. And for three centuries, skeptics have argued for the futility of the expenditure of conceptual effort with no more success than critics of the Pentagon have had in stemming the flow of funds to the military and its industrial minions. My own sympathies are with the skeptics. However, their own intense (...) involvement with the obsessions of the epistemological fear mongers and their failure to address the analogue of the problem of conversion from military to civilian industry in an acceptable manner often deprive the skeptical position of the subversive force it ought to have. (shrink)

Two books have been particularly influential in contemporary philosophy of science: Karl R. Popper's Logic of Scientific Discovery, and Thomas S. Kuhn's Structure of Scientific Revolutions. Both agree upon the importance of revolutions in science, but differ about the role of criticism in science's revolutionary growth. This volume arose out of a symposium on Kuhn's work, with Popper in the chair, at an international colloquium held in London in 1965. The book begins with Kuhn's statement of his position followed by (...) seven essays offering criticism and analysis, and finally by Kuhn's reply. The book will interest senior undergraduates and graduate students of the philosophy and history of science, as well as professional philosophers, philosophically inclined scientists, and some psychologists and sociologists. (shrink)

In this paper I discuss logic from a naturalist point of view, characterizing it as those shared patterns of thought which are socially selected from among the various patterns of thought to which we are naturally inclined. Drawing on Evans-Pritchard's anthropology. I discuss a particular example of Zande thought. I argue that Evans-Pritchard's and Timm Triplett's analyses of this example make the mistake of applying Western logic to Zande beliefs and thus find a contradiction. I argue that from the naturalistic (...) point of view. Zande logic is different from Western logic and that there is no contradiction in Zande thought. (shrink)

Certain philosophical arguments apparently show that the having of beliefs is tied conceptually to rationality. Such a view, however, seems at odds both with the possibility of irrational belief and with recent empirical discoveries in the psychology of reasoning. The aim of this paper is to move toward a reconciliation of these apparently conflicting perspectives by distinguishing between internalist and externalist conceptions of rationality. It is argued that elements of each are required for a satisfactory theory, one that allows for (...) the possibility of irrationality and makes sense of empirical findings without violating conditions on belief ascription. Normative theories, on this view, constrain the latter while remaining silent on the character of actual psychological mechanisms. (shrink)

An introduction to the model-theoretic approach in the philosophy of science is given and it is argued that this program is further enhanced by the introduction of partial structures. It is then shown that this leads to a natural and intuitive account of both "iconic" and mathematical models and of the role of the former in science itself.

We apply the recently elaborated notions of ‘pragmatic truth’ and ‘pragmatic probability’ to the problem of the construction of a logic of inductive inference. It is argued that the system outlined here is able to overcome many of the objections usually levelled against such attempts. We claim, furthermore, that our view captures the essentially cumulative nature of science and allows us to explain why it is indeed reasonable to accept and believe in the conclusions reached by inductive inference.

The object of this paper is to show why recent research in the psychology of deductive and probabilistic reasoning does not have.

Provability, Computability and Reflection.

The thirty-five chapters in this book describe various judgmental heuristics and the biases they produce, not only in laboratory experiments but in important...

The apparently paradoxical nature of self-deception has attracted a great deal of controversy in recent years. Focussing on those aspects of the phenomenon which involve the holding of "contradictory" beliefs, it is our intention to argue that this presents no "paradox" if a non-classical, "paraconsistent", doxastic logic is adopted. (On such logics, see, for example, N. C. A. da Costa, 'On the theory of inconsistent formal systems', Notre Dame J Formal Logic 11(1974), 497-510, and A. I. Arruda, 'A survey of (...) paraconsistent logic', in A. I. Arruda, N. C. A da Costa and R Chuaqui, _Mathematical Logic in Latin America, North-Holland, 1984, pp. 1-41.). (shrink)