Tacitus Annals, Book VI, XXII:
[Tacitus has just related how Tiberius consulted astrologers at his villa and had those whose competence or honesty was doubtful thrown off the cliffs into the sea below. He had then related how one astrologer, Thrasyllus, had avoided this fate by correctly foretelling it.]
For myself, when I listen to this and similar narratives, my judgement wavers. Is the revolution of human things governed by fate and changeless necessity, or by accident? You will find the wisest of the ancients, and their disciples attached to their tenets, at complete variance; in many of them [The Epicureans] a fixed belief that Heaven concerns itself neither with our origins, nor with our ending, nor, in fine, with mankind, and that so adversity continually assails the good, while prosperity dwells among the evil. Others [The Stoics] hold, on the contrary, that, though there is certainly a fate in harmony with events, it does not emanate from wandering stars, but must be sought in the principles and processes of natural causation. Still, they leave us free to choose our life: that choice made, however, the order of the future is certain. Nor, they maintain, are evil and good what the crowd imagines: many who appear to be the sport of adverse circumstances are happy; numbers are wholly wretched though in the midst of great possessions — provided only that former endure the strokes of fortunes with firmness, while the latter employ her favours with unwisdom. With most men, however, the faith is ineradicable that the future of an individual is ordained at the moment of his entry into life; …
Source: Tacitus, Annals Books IV-VI, XI-XII, Loeb Edition [Harvard 1937] translated by John Jackson.