Harvey C. Mansfield, in Taming the Prince: the Ambivalence of Modern Executive Power (Free Press, 1989), pp. 151-180

Excerpt: In Machiavelli we find the executive, but not executive power.  Before executive power could be conceived as one of the equal independent powers of a republican constitution, the very concept of power had to be discovered.  This was the work of Hobbes.  He created an abstract “power” and made it the centerpiece of political science, where it remains today. Taming the Prince: the Ambivalence of Modern Executive Power

Online:
Amazon.com