Superstition, the great enemy of truth, is said to be the result of ignorance of 'what may be and what may not be.' This is the thought which underlies and gives cogency to the whole argument. The subject of the poem is 'maiestas cognita rerum,'--the revelation of the majesty and order of the universe. The doctrine proclaimed by Lucretius was, that creation was no result of a capricious or benevolent exercise of power, but of certain processes extending through infinite time, by means of which the atoms have at length been able to combine and work together in accordance with their ultimate conditions. The conception of these ultimate conditions and of their relations to one another involves some more vital agency than that of blind chance or an iron fatalism.[421] The 'foedera naturai' are opposed to the 'foedera fati.' The idea of law in Nature, as understood by Lucretius, is not merely that of invariable sequence or concomitance of phenomena. It implies at least the further idea of a 'secreta facultas' in the original elements. This idea is not, necessarily, inconsistent with that of a creative will determining the original conditions of the elemental substances. If the ultimate principles of Lucretius were incompatible with a belief in the popular religions of antiquity, his mode of conceiving the operation of law in the universe is not irreconcileable with the conceptions of modern Theism. The idea of law not only supports the whole fabric of his physical philosophy, but moulds his convictions on human life and imparts to his poetry that contemplative elevation by which it is pervaded. It is from this ground that he makes his most powerful assault on the strongholds of superstition. Nature is thus declared to be free from the arbitrary and capricious agency of the gods:-- Libera continuo dominis privata superbis.[422] Man also is under the same law, and is made free by his knowledge and acceptance of this condition. A sense of security is thus gained for human life; a sense of elevation above its weakness and passions, and the courage to bear its inevitable evils[423]. This absolute reliance on law does not act upon his mind with the depressing influence of fatalism. Although the fortunes of life and the phases of individual character are said to be the results of the infinite combinations of blind atoms, yet man is made free by knowledge and the use of his reason. Notwithstanding the original constitution of his nature, arising out of influences over which there is no control, he still has it in his power to live a life worthy of the gods:-- Illud in his rebus videor firmare potesse, Usque adeo naturarum vestigia linqui Parvola, quae nequeat ratio depellere nobis Ut nil inpediat dignam dis degere vitam.[424]