The traditional moral concept of natural law arises in Locke's (1690) serving as a major plank in his argument regarding the basis for civil law and the protection of individual liberty, but he does not go into any detail regarding how we come to know natural law nor how we might be obligated, or even motivated, to obey it.
In his ) Locke spends little time discussing morality, and what he does provide in the way of a moral epistemology seems underdeveloped, offering, at best, the suggestion of what a moral system might look like rather than a fully-realized positive moral position.
The trick for Locke scholars has been to figure out how, or even if, they can be made to cohere. Schneewind, among others, that Locke's attempts at constructing a morality were unsuccessful.
The question is not easily settled by looking to Locke's unpublished works, either, since Locke also seems to hold a natural law view at some times and a hedonistic view at others. Schneewind does not mince words when he writes the following: “Locke's failures are sometimes as significant as his successes.
The view is not only seen by many commentators as incomplete, but it carries a degree of rationalism that cannot be made consistent with our picture of Locke as the arch-empiricist of his period.
While it is true that Locke's discussion of morality in the Essay is not as well-developed as many of his other views, there is reason to think that morality was the driving concern of this great work.
The emphasis here is on sanctions, and how rewards and punishments serve to provide morality with its normative force.
Both elements find their way into Locke's published works, and, as a result, Locke seems to be holding what seem to be incommensurable views.
His views on morality are a case in point” (Schneewind 1994, 199).
Schneewind argues that the two strands of Locke's moral theory are irreconcilable, and that this is a fact Locke must have realized.