“[Anger] pursues its intended victims with shouting and uproar, the whole body shaking, with abuse and curses added in. Reason doesn’t do this; but should the need arise, it uproots whole households — silently, quietly — and destroys families that are a plague on the commonwealth, together with their wives and children, it overturns the very dwellings and extirpates the clans that are freedom’s enemies, doing all this without gnashing its teeth or tossing its head about or any other behavior unbecoming a judge, whose expression should be calm and in repose most especially when he is making an important pronouncement.” (Book 1, 19.1-2)

Anger and reason can undertake the same actions; they just do them with different external appearances — “shouting and uproar” versus “calm and in repose”.

But there is more to this that just external appearances marking the difference. As the text continues, the shift is from direct, anger-driven violence to an administrative violence carried out bureaucratically.

Whoever is free of anger does none of these things (overturning tables, smashing cups) when imposing the penalty that each person deserves. Often he releases a person whose misdeed he has caught out: if the miscreant’s regret gives good reason to hope, if the judge sees the wickedness is not deep-seated but sticks, as they say, to the surface of the mind, he’ll grant a suspended sentence… (19.5)

The passage continues, progressing from these administrative acts of “punishment” and “correction” to full on state-administered executions:

Those whom he wants to make examples of stubborn wickedness he will make an example for all to see, not only so that they themselves will die but so that by dying they will deter others. (19.7)

While Seneca defines anger as a passion-driven desire for vengeance, it seems that reason is capable of the same desire for vengeance, it’s just that it’s calm and administrative as it carries out the retribution. This isn’t the only place in On Anger where this progression from public anger-driven violence shifts to calm, quietly executed administrative violence:

… we snuff out monstrous births and drown children too, if they’re born crippled or deformed. It’s not anger but reason to segregate the useless from the sound. (Book I, 15.2)

Reason without a proper activation of human values (found elsewhere in Seneca) becomes violent — it just works behind the scenes, “silently,quietly”.

But of course Nietzsche saw this in Socrates’ “tyranny of reason.” It’s the same tyranny that Horkheimer and Adorno found in Dialect of Enlightenment. Foucault described the same shift from public state violence (Damien the regicide) to the administrative closed-door violence of the modern prison in Discipline and Punish. The possibility and potential has always been there.