What does Plato in Book VI of The Republic (496c) refer to when writing the following words of Socrates:
My own case, the divine sign, is hardly worth mentioning—for I suppose it has happened to few or none before me.
Or within its context in Benjamin Jowett's translation:
Then, Adeimantus, I said, the worthy disciples of philosophy will be but a small remnant: perchance some noble and well-educated person, detained by exile in her service, who in the absence of corrupting influences remains devoted to her; or some lofty soul born in a mean city, the politics of which he contemns and neglects; and there may be a gifted few who leave the arts, which they justly despise, and come to her; --or peradventure there are some who are restrained by our friend Theages' bridle; for everything in the life of Theages conspired to divert him from philosophy; but ill-health kept him away from politics. My own case of the internal sign is hardly worth mentioning, for rarely, if ever, has such a monitor been given to any other man. Those who belong to this small class have tasted how sweet and blessed a possession philosophy is, and have also seen enough of the madness of the multitude; and they know that no politician is honest, nor is there any champion of justice at whose side they may fight and be saved. Such an one may be compared to a man who has fallen among wild beasts --he will not join in the wickedness of his fellows, but neither is he able singly to resist all their fierce natures, and therefore seeing that he would be of no use to the State or to his friends, and reflecting that he would have to throw away his life without doing any good either to himself or others, he holds his peace, and goes his own way. He is like one who, in the storm of dust and sleet which the driving wind hurries along, retires under the shelter of a wall; and seeing the rest of mankind full of wickedness, he is content, if only he can live his own life and be pure from evil or unrighteousness, and depart in peace and good-will, with bright hopes.