David Sanford

This comment on Steven Boer's “Object-Dependent Thoughts” develops two examples: (1) a counterexample to the "axiom of the seamlessness of truth," namely, that there are no propositions, one true and one false, such that knowing the true one requires believing the false one; (2) a story about the first sighting of Neptune, by John Galle on September 23, 1846, that illustrates how one can understand Galle's remark "That is the planet whose position Leverrier calculated" without believing that there is something to which Galle refers.

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.

Morton White proposes two patterns of expansion for sentences of the form "Possible (x is Q)" in "On What Could Have Happened" (Philosophical Review, 1968). His attempts in "Ands and Cans" (Mind, 1974) and in "Positive Freedom, Negative Freedom, and Possibility" (Journal of Philosophy, 1973) to simplify these two patterns and his argument for abandoning the first pattern are mistaken. Although I question a number of White's claims, my purpose is to improve his treatment of possibility rather than to refute it. Our understanding of what constitutes "the same circumstances" largely determines whether a given condition is appropriately mentioned in a first-pattern expansion. This point helps support the form of compatibilism White advocates.

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.

Anastylosis is the reconstruction of a monument using the original fragments and filling in the missing parts with an easily distinguishable modern material. This long review of "The Fragmentation of Reason; Preface to a Pragmatic Theory of Cognitive Evaluation" (MIT, 1990) by Stephen P Stich reconstructs, while preserving their original shapes, the conceptions of reason, truth, and rationality that Stich attempts to shatter. The review agrees with Stich's Chapter 3 which is itself highly critical of some philosophical views about evolution and rationality, and it disagrees with each of the other five chapters. Fanciful stories about food accompany and illustrate some of these disagreements.

Hume, in "An Enquiry Concerning Human Understanding", holds (1) that all causal reasoning is based on experience and (2) that causal reasoning is based on nothing but experience. (1) does not imply (2), and Hume's good reasons for (1) are not good reasons for (2). This essay accepts (1) and argues against (2). A priori reasoning plays a role in causal inference. Familiar examples from Hume and from classroom examples of sudden disappearances and radical changes do not show otherwise. A priori causal reasoning is closely related to understanding causal mechanisms. One uncovers the intelligibility of a causal process by understanding its mechanism.

Philosophers have had difficulty in explaining the difference between disjunctive and non-disjunctive predicates. Purely syntactical criteria are ineffective, and mention of resemblance begs the question. I draw the distinction by reference to relations between borderline cases. The crucial point about the disjoint predicate 'red or green', for example, is that no borderline case of 'red' is a borderline case of 'green'. Other varieties of disjunctive predicates are: inclusively disjunctive (such as 'red or hard'), disconnected (such as 'grue' on the usual definitions), and skew (such as 'grue' on an emended definition). 'Green' is not a disjunctive predicate. Nelson Goodman's new riddle of induction elicits yet another response.

McTaggart argues that the A series, which orders events with reference to past, present, and future, involves an inescapable contradiction. The significant difference between the earlier version of his argument (Mind, 1908) and the version in The Nature of Existence, Volume II, Chapter 33 (1927), has often gone unnoticed. His arguments are all invalid; the conclusion can be rejected without rejecting any premiss. It is therefore unnecessary to adopt any philosophical thesis about time (e.g., that some token-reflexive analysis of tensed statements is adequate) to avoid McTaggart's final conclusion that time is unreal.

In several works on modality, G. H. von Wright presents tree structures to explain possible worlds. Worlds that might have developed from an earlier world are possible relative to it. Actually possible worlds are possible relative to the world as it actually was at some point. Many logically consistent worlds are not actually possible. Transitions from node to node in a tree structure are probabilistic. Probabilities are often more useful than similarities between worlds in treating counterfactual conditionals.

Examples of sensory illusion show the failure of the attempt of traditional sense-datum theory to account for something's phenomenally appearing to be F by postulating the existence of a sense-datum that is actually F. the Muller-Lyer Illusion cannot be explained by postulating two sensibly presented lines that actually have the lengths the physical lines appear to have. Illusions due to color contrast cannot be explained by postulating sense-data that actually have the colors the physical samples appear to have.