Tiberius and Thrasyllus

[sdi]

Whenever [the Roman emperor Tiberius] sought counsel on [astrological] matters, he would make use of the top of the house and of the confidence of one freedman, quite illiterate and of great physical strength. The man always walked in front of the person whose science Tiberius had determined to test, through an unfrequented and precipitous path (for the house stood on rocks), and then, if any suspicion had arisen of imposture or of trickery, he hurled the astrologer, as he returned, into the sea beneath, that no one might live to betray the secret [of what Tiberius wished to divine]. Thrasyllus accordingly was led up the same cliffs, and when he had deeply impressed his questioner by cleverly revealing his imperial destiny and future career, he was asked whether he had also thoroughly ascertained his own horoscope, and the character of that particular year and day. After surveying the positions and relative distances of the stars, he first paused, then trembled, and the longer he gazed, the more was he agitated by amazement and terror, till at last he exclaimed that a perilous and well-nigh fatal crisis impended over him. Tiberius then embraced him and congratulated him on foreseeing his dangers and on being quite safe. Taking what he had said as an oracle, he retained him in the number of his intimate friends.

(Cornelius Tacitus, The Annals VI xxi, as translated by Alfred John Church)