Walter Berns, "Locke and the Legislative Principle," The Public Interest 100 (1990), 147-156.

Excerpt:

Like so many of our political principles, this idea of legislative superiority (but not supremacy) derives from John Locke’s Second Treatise of Government. Locke began, as did his predecessor Thomas Hobbes, with an analysis of the condition in which men find themselves naturally, or before government is instituted. According to Hobbes, this state of nature is indistinguishable from the state of war, where–because there is no government and because everyone has an absolute right not only to preserve himself but, as well, to whatever means are required to preserve himself–“the life of man [is] solitary, poor, nasty, brutish, and short.”

Locke’s analysis was essentially the same. “To avoid this state of war,” he wrote, “is one great reason of men’s putting themselves into society and quitting the state of nature.” True, “the state of nature has a law of nature to govern it,” and this law of nature obliges everyone “to preserve himself and … when his own preservation comes not in competition … to preserve the rest of mankind.” But in the absence of any governing authority, everyone is himself the “executioner of the law of nature,” which means, of course, that everyone is entitled to decide when self-preservation comes into competition with preserving “the rest of mankind.” The consequence, again, is war, or at least the strong possibility of war. 

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