This paper develops and draws the consequences of an etiological analysis of goal-directedness modeled on one that functions centrally in Charles Taylor's work on action. The author first presents, criticizes, and modifies Taylor's formulation, and then shows his modified formulation accounts easily for much of the fine-structure of teleological concepts and conceptualizations. Throughout, the author is at pains to show that teleological explanations are orthodox from an empiricist's point of view: they require nothing novel methodologically.

Wesley Salmon has advanced a new model of explanations of particular facts which requires that the explanans contain laws. The laws used in explanations (according to this model) are of the form P(A · C1, B) = p1 ... P(A · Cn, B) = pn. A condition imposed by Salmon on these laws is that the reference classes, i.e. A · C1 ... A · Cn, be homogenous with reference to the property B. A reference class A is homogenous with reference to a property B if every property which determines a place selection with reference to B within A is statistically irrelevant to B in A. It is argued here that the concept of homogeneity cannot in general be satisfied in scientific explanations and that even a weaker requirement, “epistemic homogeneity,” may be too strong.

In recent years there has been considerable discussion and controversy concerning the concepts of mental health and mental illness. The controversy has centered around the problem of providing criteria for an adequate conception of mental health and illness, as well as difficulties in specifying a clear and workable system for the classification, understanding, and treatment of psychological and emotional disorders. In this paper I shall examine a cluster of these complex and important issues, focusing on attempts to define ‘mental health’ and ‘mental illness’; diverse factors influencing the ascription of the predicates ‘is mentally ill’ and ‘is mentally healthy’; and some specific problems concerning these concepts as they appear in various theories of psychopathology. The approach here will be in the nature of a survey, directed at the specification of a number of problems—conceptual, methodological, and pragmatic—as they arise in various attempts to define and to provide criteria for applying the concepts of mental health and mental illness.

Independently of any eighteenth century work on the geometry of parallels, Thomas Reid discovered the non-euclidean “geometry of visibles” in 1764. Reid's construction uses an idealized eye, incapable of making distance discriminations, to specify operationally a two dimensional visible space and a set of objects, the visibles. Reid offers sample theorems for his doubly elliptical geometry and proposes a natural model, the surface of the sphere. His construction draws on eighteenth century theory of vision for some of its technical features and is motivated by Reid's desire to defend realism against Berkeley's idealist treatment of visual space.

In Chapter 4 of Science and Subjectivity, I offered several arguments critical of Professor Thomas Kuhn's views as expressed in his influential book The Structure of Scientific Revolutions. His recent replies to these criticisms seem to me so inadequate as to suggest that he, and therefore others as well, may have failed to grasp their full import. Accordingly, I shall, in the first part of this paper, briefly recapitulate my earlier arguments and offer a short rejoinder to Professor Kuhn's replies. The second part of the paper will expand upon my earlier discussion to consider the basic metaphors of vision and revolution, offered by Kuhn to replace the traditional notion of deliberation. My argument here will be that these new metaphors are incongruous in critical respects, and my discussion will conclude by considering their relations to the contrast between understanding and accepting a theory.

Building on two nonproblematic claims, I argue for a qualified endorsement of Hume's intuition that there must be a time-difference between cause and effect. Those claims are: (i) that the statement ‘A caused B’ is meaningful only if we have a criterion for saying ‘A’ and ‘B’ refer to distinct events; and (ii) that an adequate view of what it is to be an event must illuminate the enterprise of seeking to establish a singular causal statement. Specifically, I argue there must be a time-difference when cause and effect are modifications of the same physical object.

Michael Ruse has offered an interesting and insightful analysis of function statements in biology. The analysis he gives of statements of the form ‘The function of x in z is to do y‘ is :

1. (i) z does y by using x.

2. (ii) y is an adaptation ([4], p. 91).

The first thing to notice about this formulation is the peculiarity of step (ii). There are many cases in which we would naturally say that x was the adaptation, instead of y; or perhaps we might say that everything asserted in step (i) constituted the adaptation. For example, the function of the duck's webbed feet is to enable it to swim. But we would commonly and naturally say that the adaptation was the webbing, not the swimming. It seems to me that Ruse's insistence on the formulation in (ii) points to the major difficulty of his analysis : and understanding what drives him to this unnatural formulation suggests the way out of those difficulties.

In a recent paper [2] David Lewis offered an extremely interesting and, if correct, important solution to the main unsolved problem of Carnap's program for inductive logic—the choice of an appropriate C-function (=an inductive method). The gist of Lewis' solution is to first obtain a pilot sample from the target population (a time-honored procedure in statistical methodology) and then select, on the basis of this sample, from among the immodestλ-methods. An immodest inductive method is one which estimates that the mean squared error of its estimates of population relative frequencies is less than or equal that of any other inductive method. By great ingenuity Lewis apparently shows that on any evidence e there is one and only one immodest λ-method. I will attempt to show that Lewis made a conceptual error in formulating the equations to be solved and that when it is corrected it can be easily demonstrated that all admissible λ-methods are immodest and hence that Lewis' criterion is of no value.

Machines and Biology have been, since antiquity, closely related. From the zoological figures present in astronomical simulacra, through renaissance mechanical imitations of animals, through Decartes' wind pipe nerves, to present day discussions on the computer and the brain, runs a continuous thread. In fact, the very name of mechanism for an attitude of inquiry throughout the history of Biology reveals this at a philosophical level ([4] and [6]). More often than not, mechanism is mentioned in opposition to vitalism, as an assertion of the validity of the objectivity principle in biology: there are no purposes in animal nature; its apparent purposefulness is similar to the purposefulness of machines. Yet, the fact that one picks machines as a set of objects comparable to living systems, deserves a closer look. What in machines makes it possible to establish such a connection?

Professor Stevenson's valuable paper [5] calls attention to a number of discrepancies between ‘if’ in English and its usual translation into the horseshoe of material implication. “This is not a reason for distrusting the horseshoe,” he notes, “which is useful so long as it is taken to mean just what it is defined to mean; and it is not a reason for distrusting our English if's, which in spite of their ambiguities are indispensable to our daily discourse” ([5], p. 27). Accordingly, Stevenson proposes to develop a “richer logic” than the ordinary one, by adding as primitives certain sentential connectives. He speaks throughout in the old terminology of “propositions” rather than in that of the sentences or statements used to express them. Thus he speaks of atomic and molecular propositions, somehow no doubt as real entities in the world, where talk of atomic and molecular sentences would save him from implicit involvement in the notorious difficulties connected with atomic facts. Finally, the inner structure of atomic sentences, and therewith of molecular ones, is never considered. Many molecular sentences contain quantifiers in interesting ways, the clarification of which would seem essential in getting at their structure. Stevenson, however, has no concern with quantifiers, and does not exhibit the quantificational structure of the English sentences considered.

In a recent article in Philosophy of Science Janet Travis [13] seeks to refute the argument for evolutionary progressivism which is based on a series of dominant life forms on the grounds that there is no rigorous definition of that concept. In particular she claims that the definitions formulated by Sir Julian Huxley and George Gaylord Simpson fail adequately to exclude any group of organisms. The concept of dominance is therefore alleged to be meaningless and the argument for progress invalid.

(1) The probability of some generalizations can be lowered by positive instances.

(2) The change in probability (both degree and direction) can depend on factors other than the new evidence, the statement, and the probability of the statement given the old evidence.