"Again, it is possible to fail in many ways (for evil belongs to the class of the unlimited and good to that of the limited), while to succeed is possible only in one way (for which reason also one is easy and the other difficult—to miss the mark easy, to hit it difficult); for these reasons also, then, excess and defect are characteristic of vice, and the mean of virtue; For men are good in but one way, but bad in many."

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If, as I believe, the ends of men are many, and not all of them are in principle compatible with each other, then the possibility of conflict - and of tragedy - can never wholly be eliminated from human life, either personal or social. The necessity of choosing between absolute claims is then an inescapable characteristic of the human condition. This gives its value to freedom as Acton conceived of it - as an end in itself, and not as a temporary need, arising out of our confused notions and irrational and disordered lives, a predicament which a panacea could one day put right.

— Isaiah Berlin