Ch. 6. He, then, who has learned these things, and known all the angels and their causes, is rendered invisible and incomprehensible to the angels and powers, even as Caulacau also was. And as the Son was unknown to all, so must they also be known by no one; but while they know all and pass through all, they themselves remain invisible and unknown to all; for “Do thou,” they say, “know all, but let nobody know thee.” For this reason, persons of such a persuasion are also ready to recant, yea, rather, it is impossible that they should suffer on account of a mere name, since they are alike to all. The multitude, however, cannot understand these matters, but only one out of a thousand, or two out of ten thousand. They declare that they are no longer Jews, and that they are not yet Christians; and that it is not at all fitting to speak openly of their mysteries, but right to keep them secret by preserving silence. Ch. 7. They make out the local position of the three hundred and sixty-five heavens in the same way as do the mathematicians. For, accepting the theorems of the latter, they have transferred them to their own style of doctrine. They hold that their chief is Abraxas [or Abrasax]; and on this account that the word contains in itself the numbers amounting to three hundred and sixty-five. B. The School of Valentinus The Valentinians were the most important of all the Gnostics closely connected with the Church. The school had many adherents scattered throughout the Roman Empire, its leading teachers were men of culture and literary ability, and the sect maintained itself a long time. Valentinus himself was a native of Egypt, and probably educated at Alexandria, where he may have come under the influence of Basilides. He taught his own system chiefly at Rome c. 140-c. 160. The great work of Irenæus against the Gnostics, although having all Gnostics in view, especially deals with the Valentinians in their various forms, because Irenæus was of the opinion that he who refutes their system refutes all (_cf. Adv. Hær._, IV, _præf._, 2). It is difficult to reconstruct with certainty the esoteric system of Valentinus as distinguished from possibly later developments of the school, as Irenæus, the principal authority, follows not only Valentinus, but Ptolomæus and others, in describing the system. The following selection of sources gives fragments of the letters and other writings of Valentinus himself as preserved by Clement of Alexandria, passages from Irenæus bringing out distinctive features of the system, and the important letter of Ptolemæus to Flora, one of the very few extant writings of the Gnostics of an early date. It gives a good idea of the character of the exoteric teaching of the school.