Resolving the Tension in Aristotle's Ethic: The Balance Between Naturalism and Responsibility
...It is clear that there exists in the history of ethics the problem that naturalist systems of ethics frequently fall prey to the entailment of behavioral determinism. If this occurs, it robs the ethic of doing any real work. Instead of proscribing correct and incorrect action, or allowing those considering the situation and activity to meaningfully assign praise or blame, the naive naturalist ethic functions only as a psychological thesis: that one will behave according to whatever psychological or mechanical program one is informed by.
The question of this paper was whether Aristotle's system falls prey to such a difficulty given his reliance on the individual's established character as one of the bases upon which ethical decisions are made.
David E.W. Fenner. "Resolving the Tension in Aristotle's Ethic: The Balance Between Naturalism and Responsibility" Philosophy Faculty Publications (1998).
Available at: http://works.bepress.com/david_fenner/4