That language, which gives admirable expression to the dictates of common sense and to the dignified emotions which inspire the conduct of great affairs, is ill adapted both for the expression of abstract ideas and for maintaining a long process of connected argument. Lucretius has occasionally to meet the first difficulty by the adoption of Graecisms, and the second by some sacrifice of artistic elegance. Thus he uses _omne_ for τὸ πᾶν (11. 1108), _esse_, again, for τὸ εἶναι, and the like. Something of a formal and technical character appears in the links by which his argument is kept together, as in the constantly recurring use of certain connecting particles, such as the 'etenim,' 'quippe ubi,' 'quod genus,' 'amplius hoc,' 'huc accedit,' and the like. Virgil has retained some of the most striking of these connecting formulae, such as 'contemplator item,' 'nonne vides,' etc; but, as was natural in a poem setting forth precepts and not proofs, he uses them much more sparingly and with more careful selection. As used by Lucretius, they add to our sense of the vividness of the book, of the constant personal address of the author, and of his ardent polemical tone. They also keep the framework of the argument more compact and distinct: but they bring into greater prominence the artistic mistake of conducting an abstract discussion in verse. The very merits of the work considered as an argument,--its clearness, fullness, and consecutiveness,--detract from the pleasure which a work of art naturally produces. But the style cannot be too highly praised for its logical coherence and lucid illustration. The meaning of Lucretius can never be mistaken from any ambiguity in his language. There are difficulties arising from the uncertainty of the text, difficulties also from our unfamiliarity with his method and principles, or with the objects he describes, but none from confusion in his ideas or his reasoning, or from a vague or unreal use of words. II.--THE SPECULATIVE IDEAS IN LUCRETIUS. But it is in his grasp of speculative ideas, and in his application of them to interpret the living world, that the greatness of Lucretius as an imaginative thinker is most apparent. The substantial truth of all the ancient philosophies lay in the ideas which they attempted to express and embody, not in the symbols by which these ideas were successively represented. Lucretius has a place among the few adventurous thinkers of antiquity who attained to high eminences of contemplation, which were hidden from the mass of their contemporaries, and which, in the breadth of view afforded by them, are not far below the higher levels of our modern conceptions of Nature and human life. And there came to him, as to the earlier race of thinkers, that which comes so rarely to modern enquiry, the fresh and poetical sense of surprise and keen curiosity, as at the first discovery of a new country, or the first unfolding of some illimitable prospect.