  Locke's Essay concerning Human Understanding of 1690 was the first attempt to give a survey of the mind's workings that was both comprehensive and post-aristotelian. It soon fostered intense interest in epistemology, psychology and ethics. Burke seems to have worked on the imagination—the faculty of devising and combining ideas — as an undergraduate, and continued to do so into the 1750s. The result, A Philosophical Enquiry into the Origin of our Ideas of the Sublime and Beautiful (1757) emphasized, unsurprisingly, the activity of mind in making ideas and the influence of these upon conduct. It was in the first place an exercise in clarifying ideas, with an eye to refining the ways in which the arts affect the passions: in other words, a refinement of complex ideas was taken to be the precondition of a refinement of practice.