Abstract

This thesis is an investigation of the problem of skepticism with regard to the senses in David Hume's system, and of its mitigation by naturalism and abductive realism. Hume is skeptical about the view of the ordinary man, the system of the vulgar, that we know external objects directly as they are. He is also skeptical about the system of the philosophers, which assumes that there is a legitimate causal inference to the external world. Hume defends the belief in an external world on the grounds that it is a natural belief which we are psychologically compelled to believe and which we are dependent on for our existence. ;Here Hume's naturalistic defense of this belief is criticized and rejected as an inadequate defense of this belief. An abductive argument for the existence of the external world is developed which captures what is true in Hume's naturalism. ;An outline is made of Hume's epistemology and the skeptical dialectic of arguments by means of which Hume arrives at his doubts about the systems of the vulgar and the philosophers. An outline is included of the approach taken here to the mitigation of Hume's skepticism. ;After some comments are made on Hume's skeptical dialectic, some sources of Hume's skepticism are identified. Finally, Hume's attempted mitigation of skepticism by naturalism is argued to have failed. ;A critical examination of Hume's epistemology concludes that it is a main source of his skepticism. It is maintained that Hume blurs the distinction between ideas functioning as concepts as ideas functioning as mental images. An alternative account of human knowledge, that sees hypotheses and not atomic mental images as the backbone of that knowledge, is proposed. An abductive argument for the existence of the external world is developed. A circularity in standard neo-realist uses of this argument is avoided. Two further problems with the standard use of this argument; the primary/secondary quality distinction and underdeterminism, are discussed. ;The problem of underdeterminism is considered further by introducing an abductive argument for causal powers that leads to an ultimate cause