David Sanford

Suppose that Susan did not go to the movies. The reconciling project attempts to show that this plus Determinism does not imply that Susan could not have gone to the movies. The estranging project attempts to show the opposite. A counter‐entailment argument is of the form A is consistent with C, and C entails not‐B, therefore A does not entail B. An instance of the counter‐entailment arguments undermines a central argument for the reconciling project. Another instance undermines a central argument for the estranging project. This is one symmetry. In each case, the natural response to the counter‐entailment argument begs the question. This is another symmetry.

Roderick Chisholm provides, in different places, two formulations of Brentano's thesis about the relation between the psychological and the intentional: (1) all and only psychological sentences are intentional; (2) no psychological intentional sentence is equivalent to a nonintentional sentence. Chisholm also presents several definitions of intentionality. Some of these allow that a sentence is intentional while its negation is nonintentional, which ruins the prospects of defending the more plausible and interesting thesis (2). A generalization of the notion of logical independence to any number of mutually independent sentences permits a revision of Chisholm's criteria of intentionality that ensures that a sentence is intentional on a criterion exactly when its negation is as well.

Hume's arguments for the contention that causal necessity precludes logical necessity depend on the questionable principle that a cause must precede its effect. Hobbes' definition of entire cause, although it fails to account for causal priority, is not refuted by Hume. The objections of Myles Brand and Marshall Swain (Philosophical Studies, 1976) to my counterexample against Hume (Philosophical Studies, 1975) are ineffective. Their other objections to my criticisms of their argument against defining causation in terms of necessary and sufficient conditions (Synthese, 1970) are also mostly ineffective.

I criticize and emend J L Mackie's account of causal priority by replacing ‘fixity’ in its central clause by 'x is a causal condition of y, but y is not a causal condition of x'. This replacement works only if 'is a causal condition of' is not a symmetric relation. Even apart from our desire to account for causal priority, it is desirable to have an account of nonsymmetric conditionship. Truth, for example, is a condition of knowledge, but knowledge is not a condition of truth. My definitions of 'sufficient condition for' and 'necessary condition for' do not imply that p is a sufficient condition of q if and only if q is a necessary condition of p.

Fred Dretske holds that if one knows something, one need not eliminate every alternative to it but only the relevant alternatives. Besides defending this view in "The Pragmatic Dimension of Knowledge" ("Phil. Stud.", 40, 363-378, n 81), he makes some tentative suggestions about determining when an alternative is relevant. I discuss these suggestions and conclude that there are problems yet to be solved. I do not conclude that there are insoluble problems or that Dretske's approach is on the wrong track. It is, I believe, on the right track.