Socrates: Nor must one, when wronged, inflict wrong in return, as the majority believe, since one must never do worng.I always steer my students away from the strong pacifist interpretation suggested by this translation, mostly because it doesn't fit with anything else Socrates says, or his brave record as a soldier. So I am troubled to see now that most of my students are using the Grube translation. The key sentence here is "Injuring people is no different from wrongdoing." Unless I am reading things wrong, "injuring" is κακῶς ποιεῖν and "wrongdoing" is ἀδικεῖν. Now κακῶς in the firs phrase is an incredibly general term for all things bad and ἀδικεῖν is basically injustice. So literally this sentence reads "making bad on someone is the same thing as doing an injustice to them." (I'm actually rather partial to "don't make bad on people" as a moral principle.) The point is that at no point in this passage does Socrates refer to violence in purely physical terms. When he condemns something, he always uses a moral word for it. He doesn't condemn hitting people or hurting them per se; he condemns doing something immoral to them.
Crito: That seems to be the case.
Socrates: Come now, should one injure anyone or not, Crito?
Crito: One must never do so.
Socrates: Well then, if one is oneself injured, is it right, as the majority say, to inflict an injury in return, or is it not?
Crito: It is never right.
Socrates: Injuring people is no different from wrongdoing.
Crito: That is true
Am I right here? Is the Grube translation just misleading?
Update: It looks like I am getting wronger. ACW points out that I have swapped the glosses of κακῶς ποιεῖν and ἀδικεῖν. The former is wrongdoing. The latter is "injury" according to Grube, and injure "esp in medical sense" is definition 2 in the LSJ. Also, Tredennick uses "injure" in the Penguin translation. Harold North Fowler has "do evil" though.