It is also probable that between the time when the Canonical Apocalypse was written and that of Origen and Hippolytus[87], the Ophites altered their doctrines more than once. We may not be able to go so far as their historian, Father Giraud, who thinks that he can distinguish between their earlier opinions, which he would attribute to the Naassenes or Ophites[88] described by Hippolytus, and those of a later school to which he would assign the name of Ophites specially[89]. Yet many of the Fathers confuse their doctrines with those of the Sethians, the Cainites, and other sects which seem to have had some distinguishing features[90]; while Hippolytus, who shows a more critical spirit than the other heresiologists, says expressly that the other heresies just named were little different in appearance from this one, being united by the same spirit of error[91]. The confusion is further increased by his statement that the Naassenes called themselves Gnostics, although Carpocrates’ followers, who must have been later in time, are elsewhere said to be the first to adopt this name[92]. For there was at least one other sect of heretics who did the same thing, and to whom Epiphanius in his _Panarion_ attributes, together with a theological and cosmological system not unlike that hereafter described, mysteries of unnameable obscenity with which the Ophites were never charged[93]. In this respect it may be as well to remember the words of Tertullian that the heretics “know no respect even for their own leaders. Hence it is that schisms seldom happen among heretics because, even when they exist, they do not appear; for their very unity is schism. I am greatly in error,” he continues, “if they do not amongst themselves even diverge from their own rules, since every man, as it suits his own temper, modifies the traditions he has received after the same fashion as did he who handed them down to him, when he moulded them according to his own free will.... What was allowed to Valentinus is allowable to the Valentinians, and that is lawful for the Marcionites which Marcion did, _i.e._ to innovate on the faith according to his own judgment. In short, all heresies when investigated are found to be in many particulars disagreeing with their own authors[94].” If Tertullian was right, it is idle to expect that after the lapse of nineteen centuries we can hope to distinguish between the opinions of an heresiarch and those of his followers who differed from or improved upon his teaching.