8. By now I had also repudiated the lying divinations and impious absurdities of the astrologers. Let thy mercies, out of the depth of my soul, confess this to thee also, O my God. For thou, thou only (for who else is it who calls us back from the death of all errors except the Life which does not know how to die and the Wisdom which gives light to minds that need it, although it itself has no need of light--by which the whole universe is governed, even to the fluttering leaves of the trees?)--thou alone providedst also for my obstinacy with which I struggled against Vindicianus, a sagacious old man, and Nebridius, that remarkably talented young man. The former declared vehemently and the latter frequently--though with some reservation--that no art existed by which we foresee future things. But men's surmises have oftentimes the help of chance, and out of many things which they foretold some came to pass unawares to the predictors, who lighted on the truth by making so many guesses.
And thou also providedst a friend for me, who was not a negligent consulter of the astrologers even though he was not thoroughly skilled in the art either--as I said, one who consulted them out of curiosity. He knew a good, deal about it, which, he said, he had heard from his father, and he never realized how far his ideas would help to overthrow my estimation of that art. His name was Firminus and he had received a liberal education and was a cultivated rhetorician. It so happened that he consulted me, as one very dear to him, as to what I thought about some affairs of his in which his worldly hopes had risen, viewed in the light of his so-called horoscope. Although I had now begun to learn in this matter toward Nebridius' opinion, I did not quite decline to speculate about the matter or to tell him what thoughts still came into my irresolute mind, although I did add that I was almost persuaded now that these were but empty and ridiculous follies. He then told me that his father had been very much interested in such books, and that he had a friend who was as much interested in them as he was himself. They, in combined study and consultation, fanned the flame of their affection for this folly, going so far as to observe the moment when the dumb animals which belonged to their household gave birth to young, and then observed the position of the heavens with regard to them, so as to gather fresh evidence for this so-called art. Moreover, he reported that his father had told him that, at the same time his mother was about to give birth to him [Firminus], a female slave of a friend of his father's was also pregnant. This could not be hidden from her master, who kept records with the most diligent exactness of the birth dates even of his dogs. And so it happened to pass that--under the most careful observations, one for his wife and the other for his servant, with exact calculations of the days, hours, and minutes--both women were delivered at the same moment, so that both were compelled to cast the selfsame horoscope, down to the minute: the one for his son, the other for his young slave. For as soon as the women began to be in labor, they each sent word to the other as to what was happening in their respective houses and had messengers ready to dispatch to one another as soon as they had information of the actual birth--and each, of course, knew instantly the exact time. It turned out, Firminus said, that the messengers from the respective houses met one another at a point equidistant from either house, so that neither of them could discern any difference either in the position of the stars or any other of the most minute points. And yet Firminus, born in a high estate in his parents' house, ran his course through the prosperous paths of this world, was increased in wealth, and elevated to honors. At the same time, the slave, the yoke of his condition being still unrelaxed, continued to serve his masters as Firminus, who knew him, was able to report.
9. Upon hearing and believing these things related by so reliable a person all my resistance melted away. First, I endeavored to reclaim Firminus himself from his superstition by telling him that after inspecting his horoscope, I ought, if I could foretell truly, to have seen in it parents eminent among their neighbors, a noble family in its own city, a good birth, a proper education, and liberal learning. But if that servant had consulted me with the same horoscope, since he had the same one, I ought again to tell him likewise truly that I saw in it the lowliness of his origin, the abjectness of his condition, and everything else different and contrary to the former prediction. If, then, by casting up the same horoscopes I should, in order to speak the truth, make contrary analyses, or else speak falsely if I made identical readings, then surely it followed that whatever was truly foretold by the analysis of the horoscopes was not by art, but by chance. And whatever was said falsely was not from incompetence in the art, but from the error of chance.
10. An opening being thus made in my darkness, I began to consider other implications involved here. Suppose that one of the fools--who followed such an occupation and whom I longed to assail, and to reduce to confusion--should urge against me that Firminus had given me false information, or that his father had informed him falsely. I then turned my thoughts to those that are born twins, who generally come out of the womb so near the one to the other that the short interval between them--whatever importance they may ascribe to it in the nature of things--cannot be noted by human observation or expressed in those tables which the astrologer uses to examine when he undertakes to pronounce the truth. But such pronouncements cannot be true. For looking into the same horoscopes, he must have foretold the same future for Esau and Jacob, whereas the same future did not turn out for them. He must therefore speak falsely. If he is to speak truly, then he must read contrary predictions into the same horoscopes. But this would mean that it was not by art, but by chance, that he would speak truly.
For thou, O Lord, most righteous ruler of the universe, dost work by a secret impulse--whether those who inquire or those inquired of know it or not--so that the inquirer may hear what, according to the secret merit of his soul, he ought to hear from the deeps of thy righteous judgment. Therefore let no man say to thee, "What is this?" or, "Why is that?" Let him not speak thus, for he is only a man.