"The famous slogan about the strong and the weak comes, obviously, from the Athenian side of the argument, and its current popularity owes much to the nice balance between the powerful doing 'what they can' and the weak suffering 'what they must' -- as well as that iron law of inevitability (or realism, depending on your point of view) that is introduced by the phrase 'what they must.' But that is not what Thucydides wrote. As Simon Hornblower correctly acknowledges in the third and final volume of his monumental, line-by-line commentary on the whole of Thucydides' History, a more accurate translation is: 'The powerful exact what they can, and the weak have to comply.' Even that exaggerates the idea of compulsion on the weak: to be precise, what Thucydides claimed was only that 'the weak comply' -- no necessity was introduced at all. And Hornblower's commentary also raises the question of exactly what the action of the strong was supposed to be; it could equally well be translated from the original Greek as 'do' or 'exact' or even (as one Renaissance scholar thought) 'extort'. 'Do what they can' and 'extort what they can' conjure up very different pictures of the operation of power.
Does this mean that "do" "exact" or "extort" are equally possible for translation?