Abstract

Of the many disputes about Locke's views in An Essay Concerning Human Understanding, two very basic ones concern his general theory of word meaning and his position on the question of the ontological status of genera and species, or what are currently called natural kinds. In this dissertation I propose to discuss, though not settle, the first dispute. I do propose to settle the second dispute by arguing that the views in the Essay are positively anti-realist and do not entail the existence of natural kinds. ;My study of the Essay begins with an explication of Locke's central semantic thesis that words signify ideas, "the meaning of words being only the ideas they are made to stand for by him that uses them." Some major criticisms of this thesis are reviewed and ways they might be met are suggested. Once Locke's general theory of meaning has been explicated, I turn to consider its special application for those names which are predicated of natural substances, i.e., words such as 'gold,' 'water,' 'man,' 'cat,' etc. Locke's theory of the meaning of such terms hinges on his distinction between real and nominal essences, thus this discussion includes an account of Locke's view of abstraction, the process upon which the formation of nominal essences depends, as well as a brief statement of Sir Robert Boyle's corpuscular hypothesis, a theory fundamental to Locke's doctrine of real essence. Next, I survey Locke's several arguments in Book III of the Essay against the existence of kinds; these arguments are shown to provide a clear ontic denial of kinds and certain passages which are often cited as explicitly contradicting this denial are further shown to be, on the contrary, consistent with it. After considering Locke's anti-realist arguments and countering the charge that he explicitly acknowledges the reality of kinds, I turn to a refutation of the charge that Locke's doctrine of real essence is implicitly a doctrine of real kinds. Finally, I conclude by placing Locke's theories of word meaning and kinds within the larger context of the epistemological enterprise of the Essay. I also draw two important conclusions from Locke's anti-realism: that Locke does not, as has been argued by Mackie, anticipate Kripke's theory of reference and that although Locke's general theory of word meaning may have application with respect to some kinds of words, because it involves a conventionalist view of kinds, it fails to provide an account of the semantics of natural kind terms