"Locke's Doctrine of Natural Law," American Political Science Review, Vol. 52, No. 2 (June 1958). Reprinted in What Is Political Philosophy?
Let us not be shocked by this shocking self-contra- diction but rather limit ourselves to noting that according to Locke’s most frequent assertion it is only knowledge of the sensibly perceived things-of the matter, the motion and the visible structure and economy of this world-and not knowledge of virtue and vice which leads necessarily to the knowledge that some God is the author of all these things: “as soon as this (sc. the divine origin of the visible universe) is laid down, the universal law of nature [the notion of a universal law of nature] by which the human race is bound, necessarily follows [emerges]…. ” Miracles are sufficient or necessary for establishing the existence of a divine positive law; the natural law can be established only by the ascent from the ordinary course of things: “Whatever obtains among men the force of law, necessarily acknowledges either God or nature or man as its author; yet whatever either man has commanded or God has ordered by an oracle [by divine declaration], all this is positive law.” (p. 132) Natural law, we see, has its source in nature, the under- standing of which is open to man as man. Here the question arises as to the way in which “the universal law of nature binds the human race.” In his survey of the various names by which the natural law is known, Locke mentions the opinion of the majority according to which the natural law is that law which each can discover by the natural light and “to which (each) shows himself obedient in all points” (p. 110). Here the editor notes “Text doubtful” but he does not suggest an alternative translation. His translation can be defended if one assumes that Locke admitted a natural law which no man ever transgresses because no man can transgress it. The universal consent of man- kind does not prove, as Locke emphasizes in his thematic discussion of universal consent, the existence of a natural law which man can transgress; it may very well prove the existence of a natural law which no man ever does transgress (cf. p. 108).