The Metaphysics of Knowledge presents the thesis that knowledge is an absolutely fundamental relation, with an indispensable role to play in metaphysics, philosophical logic, and philosophy of mind and language. Knowledge has been generally assumed to be a propositional attitude like belief. But Keith Hossack argues that knowledge is not a relation to a content; rather, it a relation to a fact. This point of view allows us to explain many of the concepts of philosophical logic in terms of knowledge. (...) Hossack provides a theory of facts as structured combinations of particulars and universals, and presents a theory of content as the property of a mental act that determines its value for getting knowledge. He also defends a theory of representation in which the conceptual structure of a content is taken to picture the fact it represents. This permits definitions to be given of reference, truth, and necessity in terms of knowledge. Turning to the metaphysics of mind and language, Hossack argues that a conscious state is one that is identical with knowledge of its own occurrence. This allows us to characterize subjectivity, and, by illuminating the "I"-concept, allows us to gain a better understanding of the concept of a person. Language is then explained in terms of knowledge, as a device used by a community of persons for exchanging knowledge by testimony. The Metaphysics of Knowledge concludes that knowledge is too fundamental to be constituted by something else, such as one's functional or physical state; other things may cause knowledge, but do not constitute it. (shrink)

Atomism denies that complexes exist. Common-sense metaphysics may posit masses, composite individuals and sets, but atomism says there are only simples. In a singularist logic, it is difficult to make a plausible case for atomism. But we should accept plural logic, and then atomism can paraphrase away apparent reference to complexes. The paraphrases require unfamiliar plural universals, but these are of independent interest; for example, we can identify numbers and sets with plural universals. The atomist paraphrases would fail if plurals (...) presuppose complexes: but an Appendix shows that reference to complexes is not required in the semantics of plurals. (shrink)

Keith Hossack's thesis is that knowledge is a conceptually primitive and metaphysically fundamental relation between a mind and a fact. He argues that in terms of the simple relation of knowledge we can analyze central notions of epistemology, of semantics, of modality and a priori knowledge, of psychology, and of linguistics. He does so in a framework that includes a fairly rich faculty psychology and that stresses causation: knowledge can be caused by belief, but because knowledge is simple, it is (...) not any kind of belief. He regards his enterprise as metaphysics, and he proceeds in a rather grand manner. The beginning of his Preface might remind one of the opening paragraphs of Leibniz's The Monadology.If knowledge is a simple relation between minds and facts, then we want to know a bit about facts. Hossack takes facts to consist in universals being instantiated among things. He favours a view of universals as respects in which things resemble each other, but his theory is at least officially silent about which universals exist, leaving that as a matter for scientific inquiry. But he takes metaphysics to be a science. Here he is being coy, and it is worth making out how. Hossack uses multigrade relations; these are relations of no fixed polyadicity that for any natural number n may be instantiated by n things. Vectors are bearers of such relations. The relation among working men of uniting to form a union is a multigrade relation, and the founders of the International Workers of the World are a vector bearing this relation. (shrink)

The Identity Thesis, proposed by Reid for the case of sensations, and extended by Brentano to conscious states generally, says that a state is conscious iff it is identical with introspective knowledge of its own instantiation. The Thesis offers simple explanations of a number of puzzling features of introspective self-knowledge, and unites the problems of introspection, consciousness and knowledge in the single problem of the metaphysical nature of conscious states. It does nothing to solve the latter problem, but it does (...) entail that a functionalist account of consciousness is incomplete without an exact functionalist definition of knowledge itself. (shrink)

The state of affairs of some things falling under a predicate is supposedly a single entity that collects these things as its constituents. But whether we think of a state of affairs as a fact, a proposition or a possibility, problems will arise if we adopt a plural logic. For plural logic says that any plurality include themselves, so whenever there are some things, the state of affairs of their plural self-inclusion should be a single thing that collects them all. (...) This leads to paradoxes analogous to those that afflict naïve set theory. Here I suggest that they are the very same paradoxes, because sets can be reduced to states of affairs. However, to obtain a consistent theoretical reduction we must restrict the usual axiom scheme of Comprehension for plural logic to ‘stratified’ formulas, to avoid viciously circular definitions. I prove that with this modification to the background plural logic, the theory of states of affairs is consistent; moreover, it yields the axioms of the familiar set theory NFU. (shrink)

This paper develops an account of consciousness in action. Both consciousness and action are related to knowledge. A voluntary action is defined as a volition, or something intentionally effected by means of such volitions. Volitions are conscious mental acts whose proper function is to make their content true. A mental act is the exercise of a power of mind and a conscious mental act is identical with knowledge of its own phenomenal character. This set of definitions elucidates the relations between (...) consciousness, action and knowledge. (shrink)

What is exemplification? A proposition that attributes a property to an object is true if the object exemplifies the property. But according to the correspondence theory, a proposition is true if the corresponding fact exists. So if the correspondence theory is correct, an exemplification of a temporal property by an object is simply the concrete circumstance of the object’s having the property. But since not all properties are temporal, not all exemplifications are circumstances, and we need to recognise timeless as (...) well as temporal facts. This distinction allows us to solve the problem of converse relations, and to give an account of the logically complex facts which deduction allows us to know. (shrink)