Volume 10, 2007
Ancient and Modern Philosophy
Timothy M. Costelloe
"So forward to imagine"
Locke and Hume on Primary and Secondary Qualities
This paper argues that an important feature of Locke's doctrine concerning primary and secondary qualities is also central to Hume's thinking. Section one considers Locke's distinction, presenting it in terms of an "error theory." Locke argues that we attribute secondary qualities to objects and that in so doing give those qualities an ontological status they do not otherwise possess. Locke completes his theory by drawing on the concept of "resemblance" to explain why such mistakes occur in the first place. Section two turns to Hume's philosophy, arguing that, despite his ambiguous comments on Locke and "the modern philosophy," he employs an error theory of the sort developed by Locke. This contention is supported by way of Hume's treatment of beauty as a secondary quality or sentiment which arises in an individual who judges an object beautiful. The paper concludes by emphasizing that, for Hume, this philosophical explanation of beauty stands in contrast to the error committed in common life where, as in Locke's account, people make the mistake of taking beauty to be in the object itself.