When Lucretius wrote, belief in the national religion had among the upper classes become almost extinct. Those who needed conviction as a support for their life had no resource but Greek philosophy. The speculations of Plato, except in his more popular works, were not attractive to the Romans; those of Aristotle, brought to light in Cicero's time by the transference of Apellicon's library to Rome, [60] were a sealed book to the majority, though certain works, probably dialogues after the Platonic manner, gained the admiration of Cicero and Quintilian. The pre-Socratic thinkers, occupied as they were with physical questions which had little interest for Romans, were still less likely to be resorted to. The demand for a supreme moral end made it inevitable that their choice should fall on one of the two schools which offered such an end, those of the Porch and the Garden. Which of the two would a man like Lucretius prefer? The answer is not so obvious as it appears. For Lucretius has in him nothing of the _Epicurean_ in our sense. His austerity is nearer to that of the Stoic. It was the speculative basis underlying the ethical system, and not the ethical system itself, that determined his choice. Epicurus had allied his theory of pleasure [61] with the atomic theory of Democritus. Stoicism had espoused the doctrine of Heraclitus, that fire is the primordial element. Epicurus had denied the indestructibility of the soul and the divine government of the world; his gods were unconnected with mankind, and lived at ease in the vacant spaces between the worlds. Stoicism on the contrary, had incorporated the popular theology, bringing it into conformity with the philosophic doctrine of a single Deity by means of allegorical interpretation. Its views of Divine Providence were reconcilable with, while they elevated, the popular superstition. Lucretius had a strong hatred for the abuses into which state-craft and luxury had allowed the popular creed to fall; he was also firmly convinced of the sufficiency of Democritus's two postulates (_Atoms_ and _the Void_) to account for all the phenomena of the universe. Hence he gave his unreserved assent to the Epicurean system, which he expounds, mainly in its physical outlines, in his work; the ethical tenets being interwoven with the bursts of enthusiastic poetry which break, or the countless touches which adorn, the sustained course of his argument.