Attention has already been called to the fact that Epicurus, although himself indifferent to physical science, was obliged, by the demands of the age, to give it a place, and a very large place, in his philosophy. Now it was to this very side of Epicureanism that the fresh intellect of Rome most eagerly attached itself. It is a great mistake to suppose that the Romans, or rather the ancient Italians, were indifferent to speculations about the nature of things. No one has given more eloquent expression to the enthusiasm excited by such enquiries than Virgil. Seneca devoted a volume to physical questions, and regretted that worldly distractions should prevent them from being studied with the assiduity they deserved. The elder Pliny lost his life in observing the eruption of Vesuvius. It was probably the imperial despotism, with its repeated persecutions of the ‘Mathematicians,’ which alone prevented Italy from entering on the great scientific career for which she was predestined in after ages. At any rate, a spirit of active curiosity was displaying itself during the last days of the republic, and we are told that nearly all the Roman Epicureans applied themselves particularly to the physical side of their master’s doctrine.[202] Most of all was Lucretius distinguished by a veritable passion for science, which haunted him even in his dreams.[203] Hence, while Epicurus regarded the knowledge of Nature simply as a means for overthrowing religion, with his disciple the speculative interest seems to precede every other consideration, and religion is only introduced afterwards as an obstacle to be removed from the enquirer’s path. How far his natural genius might have carried the poet in this direction, had he fallen into better hands, we cannot tell. As it was, the gift of what seemed a complete and infallible interpretation of physical phenomena relieved him from the necessity of independent investigation, and induced him to accept the most preposterous conclusions as demonstrated truths. But we can see how he is drawn by an elective affinity to that early Greek thought whence Epicurus derived whatever was of any real value in his philosophy.
It has been doubted, we think with insufficient reason, that Lucretius was acquainted at first hand with Empedocles.[204] But, by whatever channel it reached him, the enthusiasm of Empedocles and the Eleates lives in his verse no less truly than the inspiration of Aeolian music in the song of his younger contemporary, Catullus. The atomic theory, with its wonderful revelations of invisible activity and unbroken continuity underlying the abrupt revolutions of phenomenal existence, had been the direct product of those earliest struggles towards a deeper vision into the mysteries of cosmic life; and so Lucretius was enabled through his grasp of the theory itself to recover the very spirit and passion from which it sprang.[205]
But the enthusiasm for science, however noble in itself, would not alone have sufficed to mould the Epicurean philosophy into a true work of art. The De Rerum Naturâ is the greatest of all didactic poems, because it is something more than didactic. Far more truly than any of its Latin successors, it may claim comparison with the epic and dramatic masterpieces of Greece and Christian Europe; and that too not by virtue of any detached passages, however splendid, but by virtue of its composition as a whole. The explanation of this extraordinary success is to be sought in the circumstance that the central interest whence Lucretius works out in all directions is vital rather than merely scientific. The true heroine of his epic is not Nature but universal life—human life in the first instance, then the life of all the lower animals, and even of plants as well. Not only does he bring before us every stage of man’s existence from its first to its last hour with a comprehensiveness, a fidelity, and a daring unparalleled in literature; but he exhibits with equal power of portrayal the towered elephants carrying confusion into the ranks of war, or girdling their own native India with a rampart of ivory tusks; the horse with an eagerness for the race that outruns even the impulse of his own swift limbs, or fiercely neighing with distended nostrils on the battlefield; the dog snuffing an imaginary scent, or barking at strange faces in his dreams; the cow sorrowing after her lost heifer; the placid and laborious ox; the flock of pasturing sheep seen far off, like a white spot on some green hill; the tremulous kids and sportive lambs; the new-fledged birds filling all the grove with their fresh songs; the dove with her neck-feathers shifting from ruby-red to sky-blue and emerald-green; the rookery clamouring for wind or rain; the sea birds screaming over the salt waves in search of prey; the snake sloughing its skin; the scaly fishes cleaving their way through the yielding stream; the bee winging its flight from flower to flower; the gnat whose light touch on our faces passes unperceived; the grass refreshed with dew; the trees bursting into sudden life from the young earth, or growing, flourishing, and covering themselves with fruit, dependent, like animals, on heat and moisture for their increase, and glad like them:—all these helping to illustrate with unequalled variety, movement, and picturesqueness the central idea which Lucretius carries always in his mind.
The keynote of the whole poem is struck in its opening lines. When Venus is addressed as Nature’s sole guide and ruler, this, from the poet’s own point of view, is not true of Nature as a whole, but it is eminently true of life, whether we identify Venus with the passion through which living things are continually regenerated, or with the pleasure which is their perpetual motive and their only good. And it is equally appropriate, equally characteristic of a consummate artist, that the interest of the work should culminate in a description of this same passion, no longer as the source of life, but as its last outcome and full flower, yet also, when pushed to excess, the illusion by which it is most utterly disappointed and undone; and that the whole should conclude with a description of death, not as exemplified in any individual tragedy, but in such havoc as was wrought by the famous plague at Athens on man and beast alike. Again, it is by the orderly sequence of vital phenomena that Lucretius proves his first great principle, the everlasting duration and changelessness of matter. If something can come out of nothing, he asks us, why is the production of all living things attached to certain conditions of place and season and parentage, according to their several kinds? Or if a decrease in the total sum of existence be possible, whence comes the inexhaustible supply of materials needed for the continual regeneration, growth, and nourishment of animal life? It is because our senses cannot detect the particles of matter by whose withdrawal visible objects gradually waste away that the existence of extremely minute atoms is assumed; and, so far, there is also a reference to inorganic bodies; but the porosity of matter is proved by the interstitial absorption of food and the searching penetration of cold; while the necessity of a vacuum is established by the ability of fish to move through the opposing stream. The generic differences supposed to exist among the atoms are inferred from the distinctions separating not only one animal species from another, but each individual from all others of the same species. The deflection of the atoms from the line of perpendicular descent is established by the existence of human free-will. So also, the analysis which distinguishes three determinate elements in the composition of the soul finds its justification in the diverse characters of animals—the fierceness of the lion, the placidity of the ox, and the timorousness of the deer—qualities arising from the preponderance of a fiery, an aërial, and a windy ingredient in the animating principle of each respectively. Finally, by another organic illustration, the atoms in general are spoken of as semina rerum—seeds of things.
At the same time Lucretius is resolved that no false analogy shall obscure the distinction between life and the conditions of life. It is for attempting, as he supposes, to efface this distinction that he so sharply criticises the earlier Greek thinkers. He scoffs at Heracleitus for imagining that all forms of existence can be deduced from the single element of fire. The idea of evolution and transformation seems, under some of its aspects, utterly alien to our poet. His intimacy with the world of living forms had accustomed him to view Nature as a vast assemblage of fixed types which might be broken up and reconstructed, but which by no possibility could pass into one another. Yet this rigid retention of characteristic differences in form permits a certain play and variety of movement, an individual spontaneity for which no law can be prescribed. The foedera Naturai, as Prof. Sellar aptly observes, are opposed to the foedera fati.[206] And this is just what might be expected from a philosophy based on the contemplation of life. For, while there is no capriciousness at all about the structure of animals, there is apparently a great deal of capriciousness about their actions. On the other hand, the Stoics, who derived their physics in great part from Heracleitus, came nearer than Lucretius to the standpoint of modern science. With them, as with the most advanced thinkers now, it is the foedera Naturai—the uniformities of co-existence—which are liable to exception and modification, while the foedera fati—the laws of causation—are necessary and absolute.
In like manner, Lucretius rejects the theory that living bodies are made up of the four elements, much as he admires its author, Empedocles. It seemed to him a blind confusion of the inorganic with the organic, the complex harmonies of life needing a much more subtle explanation than was afforded by such a crude intermixture of warring principles. If the theory of Anaxagoras fares no better in his hands, it is for the converse reason. He looks on it as an attempt to carry back purely vital phenomena into the inorganic world, to read into the ultimate molecules of matter what no analysis can make them yield—that is, something with properties like those of the tissues out of which animal bodies are composed.
Thus, while the atomic theory enables Lucretius to account for the dependent and perishable nature of life, the same theory enables him to bring out by contrast its positive and distinguishing characteristics. The bulk, the flexibility, the complexity, and the sensibility of animal bodies are opposed to the extreme minuteness, the absolute hardness, the simplicity, and the unconsciousness of the primordial substances which build them up.
On passing from the ultimate elements of matter to those immense aggregates which surpass man in size and complexity as much as the atoms fall below him, but on whose energies his dependence is no less helpless and complete—the infinite worlds typified for us by this one system wherein we dwell, with its solid earthly nucleus surrounded by rolling orbs of light—Lucretius still carries with him the analogies of life; but in proportion to the magnitude and remoteness of the objects examined, his grasp seems to grow less firm and his touch less sure. In marked contrast to Plato, Aristotle, and the Stoics, he argues passionately against the ascription of a beneficent purpose to the constitution of the world; but his reasonings are based solely on its imperfect adaptation to the necessities of human existence. With equal vigour he maintains, apparently against Aristotle, that the present system has had a beginning; against both Aristotle and Plato that, in common with all systems, it will have an end—a perfectly true conclusion, but evidently based on nothing stronger than the analogies of vital phenomena. And everywhere the subjective standpoint, making man the universal measure, is equally marked. Because our knowledge of history does not go far back, we cannot be far removed from its absolute beginning; and the history of the human race must measure the duration of the visible world. The earth is conceived as a mother bringing forth every species of living creature from her teeming bosom; and not only that, but a nursing mother feeding her young offspring with abundant streams of milk—an unexpected adaptation from the myth of a golden age. If we no longer witness such wonderful displays of fertility, the same elastic method is invoked to explain their cessation. The world, like other animals, is growing old and effete. The exhaustion of Italian agriculture is adduced as a sign of the world’s decrepitude with no less confidence than the freshness of Italian poetry as a sign of its youth. The vast process of cosmic change, with its infinite cycles of aggregation and dissolution, does but repeat on an overwhelming scale the familiar sequences of birth and death in animal species. Even the rising and setting of the heavenly bodies and the phases of the moon may, it is argued, result from a similar succession of perishing individuals, although we take them for different appearances of a single unalterable sphere.[207]
A similar vein of thought runs through the moral and religious philosophy of Lucretius. If we look on him as a reformer, we shall say that his object was to free life from the delusions with which it had been disfigured by ignorance and passion. If we look on him as an artist, we shall say that he instinctively sought to represent life in the pure and perfect beauty of its naked form. If we look on him as a poet, we shall say that he exhibits all the objects of false belief no longer in the independence of their fancied reality, but in their place among other vital phenomena, and in due subordination to the human consciousness whose power, even when it is bound by them, they reveal. But while the first alternative leaves him in the position of a mere imitator or expositor who brings home no lessons that Epicurus had not already enforced with far greater success, the other two, and above all the last, restore him to the position of an original genius, who, instead of deriving his intuitions from the Epicurean system, adopts just so much of that system as is necessary to give them coherence and shape. It may, no doubt, be urged, that were life reduced to the simple expression, the state of almost vegetative repose, demanded by Lucretius, denuded of love, of ambition, of artistic luxury, of that aspiration towards belief in and union with some central soul of things, which all religions, more or less distinctly embody, its value for imaginative purposes would be destroyed; and that the deepest lesson taught by his poem would not be how to enjoy existence with the greatest intensity, but how to abandon it with the least regret. Now it is just here that the wonderful power of poetry comes in, and does for once, under the form of a general exposition, what it has to do again and again under the easier conditions of individual presentation. For poetry is essentially tragic, and almost always excites the activity of our imagination, not by giving it the assured possession of realities, but by the strain resulting from their actual or their expected eclipse. If Homer and the Attic tragedians show us what is life, and what are the goods of life, it is not through experience of the things themselves, but through the form of the void and the outline of the shadow which their removal or obscuration has produced. So also in the universal tragedy of the Roman poet, where the actors are not persons, but ideas. Every belief is felt with more poignant intensity at the moment of its overthrow, and the world of illusion is compensated for intellectual extinction by imaginative persistence as a conscious creation, a memory, or a dream. There is no mythological picture so splendidly painted as those in which Lucretius has shown us Mavors pillowed on the lap of Venus, or led before us the Idaean mother in her triumphal car. No redeemer, credited with supernatural powers, has ever enjoyed such an apotheosis as that bestowed by his worshipper on the apostle of unbelief. Nowhere have the terrible and mysterious suggestions of mortality been marshalled with such effect as in the argument showing that death no more admits of experience than of escape. What love-inspired poet has ever followed the storm and stress of passion with such tenderness of sympathy or such audacity of disclosure, as he to whom its objects were disrobed of their divinity, for whom its fancied satisfaction was but the kindling to insaner effort of a fatally unquenchable desire? Instead of being ‘compelled to teach a truth he would not learn,’ Lucretius was enabled by the spirit of his own incomparable art to seize and fix for ever, in bold reversal of light and shade, those visions on which the killing light of truth had long before him already dawned.
The De Rerum Naturâ is the greatest of Roman poems, because it is just the one work where the abstract genius of Rome met with a subject combining an abstract form with the interest and inspiration of concrete reality; where negation works with a greater power than assertion; where the satire is directed against follies more wide-spread and enduring than any others; where the teaching in some most essential points can never be superseded; and where dependence on a Greek model left the poet free to contribute from his own imagination those elements to which the poetic value of his work is entirely due. By a curious coincidence, the great poet of mediaeval Italy attained success by the employment of a somewhat similar method. Dante represented, it is true, in their victorious combination, three influences against which Lucretius waged an unrelenting warfare—religion, the idealising love of woman, and the spiritualistic philosophy of Greece. Nevertheless, they resemble each other in this important particular, that both have taken an abstract theory of the world as the mould into which the burning metal of their imaginative conceptions is poured. Dante, however, had a power of individual presentation which Lucretius either lacked or had no opportunity of exercising; and therefore he approaches nearer to that supreme creativeness which only two races, the Greek and the English, have hitherto displayed on a very extended scale.