Hume Studies

Hume Studies Volume XXIV, Number 1, April 1998, pp. 171-194 SYMPOSIUM A version of this paper was presented at the symposium on Cognition and Commitment in Hume's Philosophy by Don Garrett, held at the XXIVth International Hume Conference, Monterey, California, July 1997. Ideas, Reason, and Skepticism: Replies to my Critics DON GARRETT I. I am grateful to my good friend Margaret Wilson for her many useful and probing questions about Hume, his predecessors, and my interpretations of them. Her questions concern three main topics: the evidence for Hume's "Copy Principle," the implications of Hume's description of abstract ideas, and the views of pre-Humean rationalists. I will try to address these three topics in that order. The Copy Principle The questions to which Wilson devotes the most attention concern Hume's evidence for the Copy Principle. This is the principle that simple ideas, and hence ultimately the complex ideas that are composed of them as well, are causally derived from simple impressions that exactly resemble those simple ideas. As Wilson observes, I claim that the Copy Principle is "a relatively straightforward empirical claim" for which the evidence "within the context of Hume's cognitive psychology is reasonably strong." She also represents me as maintaining that the Copy Principle is supportable both by "introspection" and by "more strictly empirical observations in its favor." This is not a distinction among kinds of evidence that I meant to suggest. On the contrary, I think that nearly all of Hume's evidence for the Copy Principle depends, in one way or another, on somebody's introspection— either one's own or the reported introspections of others—and I regard such Don Garrett is at the Department of Philosophy, 260 Central Campus Drive, Room 341 University of Utah, Salt Lake City UT 84112-9156 USA. email: dgarrett@rn.cc.utah.edu 172 Don Garrett introspections as being themselves fully "empirical," as I understand that term. Hume's own procedure is to argue first for what I called the Resemblance Thesis of the Copy Principle (i.e., the thesis that every simple idea has a resembling impression that corresponds to it) and then for the further Causal Thesis of the Copy Principle (i.e., the thesis that those simple ideas that resemble simple impressions are partly caused by their resembling simple impressions). In the passages where he argues most directly for the Copy Principle, Hume's explicit strategy for establishing the Resemblance Thesis is an appeal to common experience, coupled with a challenge to produce a counterexample. However, I argued that he has three main reasons for believing that this appeal (with its accompanying challenge) will be successful: (i) his confidence in Locke's and his own handling of the best-known putative counterexamples; (ii) his awareness of the prevalence of disputes about the content and implications of non-imagistic "ideas of intellect" among many of those who claim to have methodological access to them; and (iii) his belief in the adequacy of his own theory of abstract ideas to explain the generality of thought without appeal to ideas that do not resemble impressions. His evidence for the subsequent Causal Thesis may be distinguished into two kinds of cases. In cases of the first kind, someone has a specified idea and is found to have previously had the corresponding impression. In cases of the second kind, someone has not (at a given time) had a specified idea and is found not to have previously had the corresponding impression. Wilson raises two main objections to the evidence that Hume cites for his Copy Principle. The first objection is that much of the evidence, as he describes it, involves the claim that someone has previously had an impression with a certain content, even though impressions themselves are notoriously fleeting. Humean memory produces only ideas; it does not literally reproduce past impressions for direct comparison. So, Wilson concludes, "there is something like a conceptual absurdity...in the enterprise of trying to determine whether [an idea] was or was not copied exactly from an impression." I agree that the Humean faculty of memory uses ideas to represent certain objects—including impressions with certain contents—as having...