here. In some other works of sf, like Greg Bear's Eon and John C. Wright's The Golden Age, this inner control is gained by technological means:
"...Phaeton tended to use some small glandular and parasympathetic regulators. But now, with that support gone, it was almost like being drunk. Despair and frustration raged within his brain, and he had no automatic way to turn those emotions off."
-John C. Wright, The Golden Age (New York, 2003), p. 141.
There should be a solution:
"Phaeton took a deep breath, fighting for calmness. Everyone in the ancient world used to control themselves naturally, organically, without any cybernetic assistance. If they could do it, he could do it!" (ibid.)
However, suddenly stabbed and surprised by blinding anger, Phaeton reflects:
"(...the ancient world had been turbulent with war and crime and insanity, not once or twice but at all times. Maybe, this self-control stuff was more difficult than it seemed.)" (pp. 141-142)
We could have told him that! Wright simultaneously imagines a future and comments on the present, the two roles of an sf writer.