Love of power, operating through greed and through personal ambition, was the cause of all these evils. To this must be added the violent fanaticism which came into play once the struggle had broken out. Leaders of parties in the cities had programmes which appeared admirable – on one side political equality for the masses, on the other the safe and sound government of the aristocracy – but in professing to serve the public interest they were seeking to win the prizes for themselves. In their struggles for ascendancy nothing was barred; terrible indeed were the actions to which they committed themselves, and in taking revenge they went farther still. Here they were deterred neither by the claims of justice nor by the interests of the state; their one standard was the pleasure of their own party at that particular moment, and so, either by means of condemning their enemies on an illegal vote or by violently usurping power over them, they were always ready to satisfy the hatreds of the hour. Thus neither side had any use for conscientious motives; more interest was shown in those who could produce attractive arguments to justify some disgraceful action. As for the citizens who held moderate views, they were destroyed by both the extreme parties, either for not taking part in the struggle or in envy at the possibility that they might survive.

(Sthenelaidas:) If they behaved well in the Persian War and are now behaving badly to us they ought to be punished twice over, because they were once good men and have become bad.
(Book 1 Chapter 86.1)

And we are wise because we are not so highly educated as to look down upon our laws and customs, and are too rigorously trained in self-control to be able to disobey them. We are trained to avoid being too clever in matters that are of no use – such as being able to produce an excellent theoretical criticism of one’s enemies’ dispositions, and then failing in practice to do quite so well against them. Instead we are taught that there is not a great deal of difference between the way we think and the way others think, and that it is impossible to calculate accurately events that are determined by chance.