Augustine, Confessions §aug_conf_07_009: Upon hearing and believing these things, told by one of such credibility, all...
Upon hearing and believing these things, told by one of such credibility, all that my resistance gave way; and first I endeavoured to reclaim Firminus himself from that curiosity, by telling him that upon inspecting his constellations, I ought if I were to predict truly, to have seen in them parents eminent among their neighbours, a noble family in its own city, high birth, good education, liberal learning. But if that servant had consulted me upon the same constellations, since they were his also, I ought again (to tell him too truly) to see in them a lineage the most abject, a slavish condition, and every thing else utterly at variance with the former. Whence then, if I spake the truth, I should, from the same constellations, speak diversely, or if I spake the same, speak falsely: thence it followed most certainly that whatever, upon consideration of the constellations, was spoken truly, was spoken not out of art, but chance; and whatever spoken falsely, was not out of ignorance in the art, but the failure of the chance.