Plutarch, Nicias
Bernadotte Perrin, Ed.

But just as everything was prepared for this and none of the enemy were on the watch, since they did not expect the move at all, there came an eclipse of the moon by night. This was a great terror to Nicias and all those who were ignorant or superstitious enough to quake at such a sight. The obscuration of the sun towards the end of the month was already understood, even by the common folk as caused somehow or other by the moon; [2] but what what it was that the moon encountered, and how, being at the full, she should on a sudden lose her light and emit all sorts of colors, this was no easy thing to comprehend.

The first man to put in writing the clearest and boldest of all doctrines about the changing phases of the moon was Anaxagoras. But he was no ancient authority, nor was his doctrine in high repute. It was still under seal of secrecy, and made its way slowly among a few only, who received it with a certain caution rather than with implicit confidence. [3] Men could not abide the natural philosophers and ‘visionaries,’ as they were then called, for that they reduced the divine agency down to irrational causes, blind forces, and necessary incidents. Even Protagoras had to go into exile,¹ Anaxagoras was with difficulty rescued from imprisonment by Pericles,² and Socrates, though he had nothing whatever to do with such matters, nevertheless lost his life³ because of philosophy. [4] It was not until later times that the radiant repute of Plato, because of the life the man led, and because he subjected the compulsions of the physical world to divine and more sovereign principles, took away the obloquy of such doctrines as these, and gave their science free course among all men. At any rate, his friend Dion, although the moon suffered an eclipse at the time when he was about to set out from Zacynthus on his voyage against Dionysius, was in no wise disturbed, but put to sea, landed at Syracuse, and drove out the tyrant.⁴ [5]

However, it was the lot of Nicias at this time to be without even a soothsayer who was expert. The one who had been his associate, and who used to set him free from most of his superstition, Stilbides, had died a short time before. For indeed the sign from Heaven, as Philochorus observed, was not an obnoxious one to fugitives, but rather very propitious; concealment is just what deeds of fear need, whereas light is an enemy to them. [6] And besides, men were wont to be on their guard against portents of sun and moon for three days only, as Autocleides has remarked in his ‘Exegetics’; but Nicias persuaded the Athenians to wait for another full period of the moon, as if, forsooth, he did not see that the planet was restored to purity and splendor just as soon as she had passed beyond the region which was darkened and obscured by the earth.