Dating Adam Smith's Essay "Of the External Senses"

Abstract

According to the received view, Adam Smith's essay the External Senses was written sometime before 1752. The evidence for this claim comes from the fact that this essay argues for a distinction between primary and secondary qualities of material objects, a distinction which was denied by Berkeley in his Principles ofHuman Knowledge (1710). However, Smith did commend Berkeley's Essay towards a New Theory of Vision (1709), thus the presumption is that Smith maintained the primacy of solidity, extension, etc. only because he was not familiar with Berkeley's later argument. It is therefore probable that he wrote the essay before digesting Hume's Treatise (1739) or even before becoming closely acquainted with Hume, as there is reason to believe he did before 1752 (Stewart, 1.13).'1 Of course this line of reasoning hinges upon the idea that Smith would have agreed with Hume's and Berkeley's analyses of the sensory origin of knowledge, but this assumption must be questioned simply because it is certain that the essay was written during or after the year 1758, a late enough date that we can reasonably assume that Smith was well aware of Berkeley's idealist argument against the distinction between primary and secondary qualities of bodies, either directly or via Hume. The evidence for this lower bound of 1758 comes from the essay itself, particularly Smith's various references to Linnaeus's Systema Naturae.2 As is well known, the great Swedish botanist Carolus Linnaeus was the first naturalist successfully to organize all the known plants and animals into their class, order, genus, and species, although the English naturalists John Ray and Francis Willughby had undertaken the same task a half-century earlier. This