Lectures delivered at the Johns Hopkins University in 1975. Includes bibliographical references and index.

If two statements are contraries if and only if they cannot both be true, but can both be false, then some corresponding A and E categorical statements are not contraries, even on the presupposition that something exists which satisfies the subject term. For some such statements are necessarily true and thus cannot be false. There is a similar problem with subcontraries.

The primary objects of hearing are sounds: everything we hear we hear by hearing a sound. (This claim differs from Berkeley’s that we hear only sounds and from Aristotle’s that we only hear sounds.) Colored regions are primary objects of sight, and pressure resistant regions are primary objects of perception by touch. By definition, the primary objects of perception are physical. The properties of the primary objects of perception are exactly the properties sense-datum theories attribute to sense-data. Indirect Realism holds (...) that awareness of sense-data (or something similar) mediates our perception of primary objects. Direct Realism denies this. The question when the perception of a primary object, such as parts of the surfaces of a hat and coat, is thereby the perception of a non-primary object, such as a person, is independent of the disagreement between Direct and Indirect Realism. (shrink)

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.

This new edition includes three new chapters, updating the book to take into account developments in the field over the past fifteen years.

Naive mereology studies ordinary, common-sense beliefs about part and whole. Some of the speculations in this article on naive mereology do not bear directly on Peter van Inwagen's "Material Beings". The other topics, (1) and (2), both do. (1) Here is an example of Peter Unger's "Problem of the Many". How can a table be a collection of atoms when many collections of atoms have equally strong claims to be that table? Van Inwagen invokes fuzzy sets to solve this problem. (...) I claim that an alternative treatment of vagueness, supervaluations over many-value valuations, provides a better solution. (2) The Special Composition Question asks how parts compose a whole. One who rejects van Inwagen's answer in terms of constituting a life need not provide some alternative answer. Even if all answers to the Special Question fail, there are a multitude of less general composition questions that are not so difficult. (shrink)

Wittgenstein remarks in the "Tractatus" that the eye is not in the visual field. I question the claim of Michael Dummett and P T Geach that reflection on this remark helps one conceive of an observer perceiving objects in space without having any location in that space. The literal meaning of "point of view" is illustrated by the visual field. Reflection on the fact that the point of view is not itself normally an object of sight is no help in (...) conceiving perception from no point of view. (shrink)

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. (shrink)

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. (shrink)

In "Causes and "If P, Even If X, still Q," Philosophy 57 (July 1982), Ted Honderich cites my "The Direction of Causation and the Direction of Conditionship," journal of Philosophy 73 (April 22, 1976) as an example of an account of causal priority that lacks the proper character. After emending Honderich's description of the proper character, I argue that my attempt to account for one-way causation in terms of one-way causal conditionship does not totally lack it. Rather than emphasize the (...) singularity of an effect, as Honderich does, I emphasize the multiplicity of independent factors in a causal circumstance. (shrink)

A primary purpose of argument is to increase the degree of reasonable confidence that one has in the truth of the conclusion. A question begging argument fails this purpose because it violates what W. E. Johnson called an epistemic condition of inference. Although an argument of the sort characterized by Robert Hoffman in his response (Analysis 32.2, Dec 71) to Richard Robinson (Analysis 31.4, March 71) begs the question in all circumstances, we usually understand the charge that an argument is (...) question begging with reference to the beliefs of the person, or the sort of person, to whom the argument is directed. (shrink)

Twenty-one paragraphs in this entry begin with a statement of a view about causation. To help organize the entry, the next sentence then classifies the view as 'prevailing, majority, controversial', or 'minority'. The following brief discussions attempt to be clear and fair. Respect for fairness, however, does not prevent the author from referring to his own views. For example, the author classifies "There is no element of genuine a priori reasoning in causal inference" as a majority view. After expounded the (...) central reasons for this majority view, he goes on to criticize these reasons. (shrink)

The central text of this article is Thomas Reid’s response to Berkeley’s argument for distinguishing tangible from visual shape. Reid is right to hold that shape words do not have different visual and tangible meanings. We might also perceive shape, moreover, with senses other than touch and sight. As Reid also suggests, the visual perception of shape does not require perception of hue or brightness. Contrary to treatments of the Molyneux problem by H. P. Grice and Judith Jarvis Thomson, I (...) argue that breakdowns of a certain kind between tangible and visible shape are conceivable. (shrink)

This article answers John Biro's "Knowability, Believability, and Begging the Question: a Reply to Sanford" in "Metaphilosophy" 15 (1984). Biro and I agree that of two argument instances with the same form and content, one but not the other can beg the question, depending on other factors. These factors include actual beliefs, or so I maintain (against Biro) with the help of some analysed examples. Brief selections from Archbishop Whatley and J S Mill suggest that they also regard reference (...) to actual beliefs as essential to explaining begging the question. (shrink)

Two fusions can be in the same place at the same time. So long as a house made of Tinkertoys is intact, the fusion of all its Tinkertoys parts coincides with the fusion of it walls and its roof. If none of the Tinkertoys is destroyed, their fusion persists through the complete disassembly of the house. (So the house is not a fusion of its Tinkertoy parts.) The fusion of the walls and roof does not persist through the complete disassembly (...) because the walls and the roof themselves do not persist. (So the walls and the roof are also not fusions of their Tinkertoy parts.). (shrink)

Many philosophic arguments concerned with infinite series depend on the mutual inconsistency of statements of the following five forms: (1) something exists which has R to something; (2) R is asymmetric; (3) R is transitive; (4) for any x which has R to something, there is something which has R to x; (5) only finitely many things are related by R. Such arguments are suspect if the two-place relation R in question involves any conceptual vagueness or inexactness. Traditional sorites arguments (...) show that a statement of form (4) can fail to be true even though it has no clear counter-example. Conceptual vagueness allows a finite series not to have any definite first member. I consider the speculative possibilities that there have been only finitely many non-overlapping hours although there has been no first hour and that space and time are only finitely divisible even though there are no smallest spatial or temporal intervals. (shrink)

Myles Brand and Marshall Swain advocate the principle that if A is the set of conditions individually necessary and jointly sufficient for the occurrence of B, then if C is a set of conditions individually necessary for the occurrence of B, every member of C is a member of A. I agree with John Barker and Risto Hilpinen who each argue that this principle is not true for causal necessity and sufficiency, but I disagree with their claim that it is (...) true for logical necessity and sufficiency. The original appeal of the principle may be due to confusing two kinds of totality: to say that when every member of set A obtains, then every condition necessary for E obtains is not to say that every condition necessary for E is a member of A. All the authors mentioned believe that causal necessity precludes logical necessity. I deny this on the basis of an example from kinematics. Hume has not refuted definitions of causation in terms of logically necessary and sufficient conditions, nor have Brand and Swain. (shrink)

Time and cause present apparent asymmetries. What happens later depends on what happens earlier, and not the other way around. Effects depend on their causes, and not the other way around.

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. (shrink)

According to John A Barker, whether an argument begs the question is purely a matter of logical form. According to me, it is also a matter of epistemic conditions; some arguments which beg the question in some contexts need not beg the question in every context. I point out difficulties in Barker's treatment and defend my own views against some of his criticisms. In the concluding section, "Alleged difficulties with disjunctive syllogism," I defend the validity of disjunctive syllogism against the (...) views of Alan Ross Anderson and Nuel D Belnap, Jr., ask pointed questions about the notion of intensional disjunction, and suggest how my treatment of begging the question can be extended to deal with the so-called paradoxes of strict implication. (shrink)

Everything red is colored, and all squares are polygons. A square is distinguished from other polygons by being four-sided, equilateral, and equiangular. What distinguishes red things from other colored things? This has been understood as a conceptual rather than scientific question. Theories of wavelengths and reflectance and sensory processing are not considered. Given just our ordinary understanding of color, it seems that what differentiates red from other colors is only redness itself. The Cambridge logician W. E. Johnson introduced the terms (...) determinate and determinable to apply to examples such as red and colored. Chapter XI, of Johnson's Logic, Part I (1921), “The Determinate and the Determinable,” is the main text for discussion of this distinction. (shrink)

Locke thought it was a necessary truth that no two material bodies could be in the same place at the same time. Leibniz wasn't so sure. This paper sides with Leibniz. I examine the arguments of David Wiggins in defense of Locke on this point (Philosophical Review, January 1968). Wiggins’ arguments are ineffective.

Sam signaled a turn by extending his arm out the window. Difficulties in explaining the asymmetry of the by-relation in such examples by reference to acceptable and unacceptable counterfactual conditionals are explored by Hugh McCann in "The Trouble with Level-Generation" ("Mind", October 1982). I refine and defend the following alternative account of one-way dependence of y on x: not only is x necessary for y, but something else, independent from x, is also necessary for y; but there is nothing independent (...) from y such that it and y are each necessary for x. (shrink)

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. (shrink)

I revise J L Mackie's first account of casual direction by replacing his notion of "fixity" by a newly defined notion of "sufficing" that is designed to accommodate indeterminism. Keeping Mackie's distinction between casual order and casual direction, I then consider another revision that replaces "fixity" with "one-way conditionship". In response to the charge that all such accounts of casual priority beg the question by making an unjustified appeal to temporal priority, i maintain that one-way conditionship explains rather that assumes (...) objective temporal dependence as well as objective casual dependence. (shrink)

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. (shrink)

This piece continues the story line of “Where Am I?” by Dan Dennett. I am inclined to locate myself at the location of my point of view. In my fantasy stories, points of view can be far away from a brain inside a flesh-and-blood body. Points of view can also move discontinuously from one location to another.

A statement q is a conclusion intermediate between p and h if and only if (1) p justifies h, (2) p justifies q, and (3) (p and not-q) justifies h to a significantly lesser degree than p justifies h. I contend that Gettier-type counterexamples to definitions of factual knowledge violate the following principle: if one knows that h on the basis of p, then all the conclusions intermediate between p and h are true. This principle does not refer to anyone's (...) beliefs that intermediate conclusions are true. I test my contention against several examples which have been discussed in the literature. (shrink)

Although the truth value (falsity) of "Henry knows that (dogs live in trees and beavers chew wood)" remains unchanged no matter what sentence is substituted in it for "beavers chew wood", we want not to regard the second as a truth functional component (tfc) of the first. Many definitions of "tfc" (e.g., Quine's) fail to insure satisfaction of the following principle: if p is a component of r which is in turn a component of q, then p is a tfc (...) of q if and only if 1) p is also a tfc of r, and 2) r is also a tfc of q. (shrink)

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. (shrink)

If there are vague numbers, it would be easier to use numbers as semantic values in a treatment of vagueness while avoiding precise cut-off points. When we assign a particular statement a range of values (less than 1 and greater than 0) there is no precise sharp cut-off point that locates the greatest lower bound or the least upper bound of the interval, I should like to say. Is this possible? “Vague Numbers” stands for awareness of the problem. I do (...) not present a serious theory of vague numbers. I sketch some reasons for using a many-value semantics. These reasons refer to my earlier treatments of determinacy and definitions of higher-order borderline cases. I also sketch how definitions of independence use the determinacy operator. The distinction between actually assigned values and values whose assignments are acceptable helps avoid unwanted precise cut-off points. (shrink)

To accommodate vague statements and predicates, I propose an infinite-valued, non-truth-functional interpretation of logic on which the tautologies are exactly the tautologies of classical two-valued logic. iI introduce a determinacy operator, analogous to the necessity operator in alethic modal logic, to allow the definition of first-order and higher-order borderline cases. On the interpretation proposed for determinacy, every statement corresponding to a theorem of modal system T is a logical truth, and I conjecture that every logical truth on the interpretation corresponds (...) to a theorem of T. the interpretation is extended to predicate logic. A borderline case of a predicate 'F’ is neither determinately F nor determinately not-F. Traditional sorites arguments are seen to fall apart early in their gradual stepwise passage from truth to falsity. (shrink)