Hellenica (2.3.25-2.3.29)

Now we, believing that for men like ourselves and you democracy is a grievous form of government, and convinced that the commons would never become friendly to the Lacedaemonians, our preservers, while the aristocrats would continue ever faithful to them, for these reasons are establishing, with the approval of the Lacedaemonians, the present form of government.

And if we find anyone opposed to the oligarchy, so far as we have the power we put him out of the way; but in particular we consider it to be right that, if any one of our own number is harming this order of things, he should be punished.

Now in fact we find this man Theramenes trying, by what means he can, to destroy both ourselves and you. As proof that this is true you will discover, if you consider the matter, that no one finds more[*] fault with the present proceedings than Theramenes here, or offers more opposition when we wish to put some demagogue out of the way. Now if he had held these views from the beginning, he was, to be sure, an enemy, but nevertheless he would not justly be deemed a scoundrel.

In fact, however, he was the very man who took the initiative in the policy of establishing a cordial understanding with the Lacedaemonians; he was the very man who began the overthrow of the democracy, and who urged you most to inflict punishment upon those who were first brought before you for trial; but now, when you and we have manifestly become hateful to the democrats, he no longer approves of what is going on,—just so that he may get on the safe side again, and that we may be punished for what has been done.

Therefore he ought to be punished, not merely as an enemy, but also as a traitor both to you and to ourselves. And treason is a far more dreadful thing than war, inasmuch as it is harder to take precaution against the hidden than against the open danger, and a far more hateful thing, inasmuch as men make peace with enemies and become their trustful friends again, but if they catch a man playing the traitor, they never in any case make peace with that man or trust him thereafter.