In the previous parts of this study we examined the works of Whichcote, Cudworth, Shaftesbury, and Hutcheson. There were many differences between those thinkers. But in certain highly significant respects all of them stand together on one side of a philosophical divide, while David Hume stands alone on the other. In this chapter I outline three related ways in which Hume's Treatise account of morality and human nature differs from the work of his predecessors. In Chapters 16 to 19 I examine the specific arguments that set the Treatise apart. And in Chapter 20 I point to some implications Hume's new account has for our thinking about morality and human nature.

Theoretical, Not Practical

The Treatise differs from the writings of earlier British moralists, first of all, in being an essentially theoretical work, not a practical one. The goal of the Treatise is to provide an account that best captures the observable phenomena of human behavior. It does not try to convince people that they ought to act in certain ways. The Treatise will succeed if it advances our understanding of human conduct. Its success does not depend on improving our conduct.

Virtually all previous moral philosophy, in contrast, had been explicitly practical. The goal of Hume's predecessors was to improve their readers' conduct. This was true of proponents of both the Negative and Positive Answers.

The practical purpose of the Negative Answer is perfectly clear in the writings of Hobbes and the English Calvinists.