"Marsilius of Padua," History of Political Philosophy, ed., Leo Strauss and Joseph Cropsey, Rand McNally, 1963.  Second Edition: Rand McNally, 1972.  Third Edition, University of Chicago Press, 1987.

Excerpt:

As regards the principles of political philosophy, Marsilius presents himself as a strict follower of Aristotle, “the divine philosopher” or “the pagan sage.” He explicitly agrees with Aristotle regarding the purpose of the commonwealth : the commonwealth exists for the sake of the good life, and the good life consists in being engaged in the activity becoming a free man, i.e., in the exercise of the virtues of the practical as well as of the speculative soul. While practical or civic felicity “seems to be” the end of human acts, in fact the activity of the metaphysician is more perfect than the activity of the prince who is the active or political man par excellence. Marsilius explicitly agrees with Aristotle in regarding the purpose of the commonwealth as the ground for the other kinds of causes (material, formal, and moving) of the commonwealth and of its parts. He explicitly agrees with him in very many other points. He has only one reservation against Aristotle : Aristotle did not know one very grave disease of civil society, an “evil thing, the common enemy of the human race” which must be eradicated. This ignorance does not derogate from Aristotle’s supreme wisdom. Aristotle did not know the “pestilence” in question because he could not know it, for it was the accidental consequence of a miracle and it could have been even less foreseen by the wisest man than the miracle itself. The miracle was the Christian revelation, and the grave disease arose from the claims. in no way supported by Scripture, of the Christian hierarchy-claims which culminate in the notion of papal plenitude of power. Marsilius declares that this is the only political disease with which he will deal, since the others have been properly dealt with by Aristotle’s One ought therefore not even to expect to find a -complete presentation of political philosophy in the Defender. The work comes to sight as a kind of appendix to that part of Aristotle’s Politics which may he said to deal with the diseases of civil society.

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