While Plutarch, in his anxiety to safeguard the emotional aspects of Religion from the incursions of Superstition, departs in this tract from his ordinary attitude of intellectual moderation, he reverts very markedly to his usual manner in his treatise on the two Egyptian divinities, Isis and Osiris. Knowledge of the Truth is here depicted as the very heart of devotion, and the pursuit of this is regarded as the only means of holding a middle path between the bog of Superstition and the precipice of Atheism. The main object of this treatise is to show how principles of rational inquiry may be applied to religious myths, so that Reason and Piety may both be satisfied with the result. Wyttenbach explains this purpose in a few words of terse Latinity which might safely be quoted as descriptive of Plutarch’s attitude towards Religion in general. “_Consilium scriptoris videtur fuisse, ut amicam de horum Ægyptiorum numinum ortu et cultu saniora, quam quæ vulgo ferrentur, doceret, religionemque fabularum deliriis cærimoniarumque ineptiis mirifice deformatam et apud prudentiores homines in contemtum adductam, istis quoad ejus fieri posset sordibus purgaret, omnique literarum et philosophiæ instrumento ad historiæ fidem, naturæ rationem dignamque divinitate speciem reformaret._” But while serving as an example of Plutarch’s general method of inquiry, a particular motive for the choice of this special myth as subject would doubtless be furnished by the great prevalence and popularity of the worship of Isis during the Græco-Roman Empire of this period. Its passionate excitements were hostile to the calm cultivated by the Roman in matters of Religion, and Isis had undergone a prolonged struggle before her temples were allowed to stand erect in Rome. The patrician indignation of Lucan—_nos in templa tuam Romana accepimus Isin!_[344]—expressed, however, rather the sentiment of the Republic than the conviction of the Empire. Juvenal alludes to the _Isiacæ sacraria lenæ_—the _fanum Isidis_—the temple of the goddess in the Campus Martius, in terms which, however severe from the moral standpoint, leave no historical doubt as to the established character of the cult and its institutions. In the later romance of Apuleius, the hero Lucius owes his re-transformation into human shape to the power of Isis, and makes a pilgrimage of gratitude to the very temple to which Juvenal makes so scathing an allusion.