Fate does control, yes, but only punishes those who fly in the face of all that is just and divine. For instance, Plato would agree with Sophocles that Fate would have a hand in punishing those who rule via hubris, or supreme confidence in their wisdom and strengths. However, Plato believed that through acting justly and with proper political and logical behavior, humans can actually reroute fate and escape its wrath. Aristotle was, arguably, the most different in his beliefs on how humans should behave, and the construction of their education, in this group of Plato, Sophocles and Aristotle.

By setting up objective criteria for human behavior, Aristotle prepares the foundation for his aristocratic political views. Perhaps the part of Aristotle's Politics most offensive to the general concept of Greek democracy is his defense of slavery. Aristotle, in that view, was a true aristocrat (yes, hence the term) as far as patterns of human behavior go.

Aristotle suggests the existence of natural slaves, "those who are as different [from other men] as the soul from the body or man from the beast,... who [participate] in reason only to the extent of perceiving it, but [do] not have it." This justification of slavery, however, does not follow from Aristotle's logic but rests on an outside claim that such slaves by nature...

In this regime, the aristocracy of gentlemen, only a small class of elites are citizens and share in the responsibilities of guiding behavior, while the majority of the people are slaves, doing manual work to maintain the city and produce the necessary sustainable living. This process sounds a lot like Sparta's ideal.
With such elements as these forming a part of Aristotle's political theory, it is clear why conventional Greek thinkers want to avoid such a view. Still, the liberal project fails to resolve the problem of safeguarding freedom and equality in that it attempts to justify individual rights and behaviors without providing any underlying philosophical basis for those rights.

The education of human behavior for Aristotle is an inculcation of the fact that certain people are born to rule and guide behavior and other people simply do not have, and will not have, the ability to do so. That is what we should simply accept. Alexander Hamilton later adopted the philosophy in America in his theory that only landed gentry should rationalize.

So, therein lie the critical differences between Aristotle, Sophocles and Plato on human behavior: Plato and Sophocles both believe in the just ruler and the idea of behavioral comportment that does not fly in the face of Fate - i.e., no hubris - and if indeed there is a contravention, Fate will eventually punish. Aristotle believes that the education of human behavior should be divided out into the ruling classes and the slave classes, with the ruling classes educating on human behavior for both groups.