The Seven Books of Arnobius Against the Heathen: Book IV. 15Chapter XV.

15. And lest it should seem tedious and prolix to wish to consider each person singly, the same theologians say that there are four Vulcans and three Dianas, as many AEsculapii and five Dionysi, six Hercules and four Venuses, three sets of Castors and the same number of Muses, three winged Cupids, and four named Apollo; whose fathers they mention in like manner, in like manner their mothers, and the places where they were born, and point out the origin and family of each. But if it is true and certain, and is told in earnest as a well-known matter, either they are not all gods, inasmuch as there cannot be several under the same name, as we have been taught; or if there is one of them, he will not be known and recognised, because he is obscured by the confusion of very similar names. And thus it results from your own action, however unwilling you may be that it should be so, that religion is brought into difficulty and confusion, and has no fixed end to which it can turn itself, without being made the sport of equivocal illusions.