Full Idea
Men should be either treated generously or destroyed, because they take revenge for slight injuries.
Gist of Idea
People are vengeful, so be generous to them, or destroy them
Source
Niccolo Machiavelli (The Prince [1513], Ch.3)
Book Reference
Machiavelli,Niccolo: 'The Prince, selections from Discourses', ed/tr. Plamenatz,J [Fontana 1972], p.62
A Reaction
This sounds like good advice, and works quite well in school teaching too. It seems like advice drawn from the growth of the Roman Empire, rather than from dealing with sophisticated and educated people.