On Anger, Book 1, Section 17 — In Plain English

Seneca — The Senator

Anger hits hardest at first. It's like a snake that just woke up — its first bite is the most venomous. After a few strikes, the poison runs out and becomes harmless. So people who commit the same crime don't get the same punishment. Often someone who did less wrong gets punished more harshly, simply because they caught anger while it was still fresh. Anger is completely unpredictable. Sometimes it goes way too far. Other times it doesn't do enough. It follows its own whims and makes decisions based on mood. It won't listen to evidence. It won't let anyone defend themselves. It grabs onto wrong assumptions and refuses to let go, even when it's clearly mistaken.

Seneca — The Senator Original

Its first onset is fierce, just as the teeth of snakes when first roused from their lair are venomous, but become harmless after repeated bites have exhausted their poison. Consequently those who are equally guilty are not equally punished, and often he who has done less is punished more, because he fell in the way of anger when it was fresher. It is altogether irregular; at one time it runs into undue excess, at another it falls short of its duty: for it indulges its own feelings and gives sentence according to its caprices, will not listen to evidence, allows the defence no opportunity of being heard, clings to what it has wrongly assumed, and will not suffer its opinion to be wrested from it, even when it is a mistaken one.