The word nature has many senses; but if we preserve the one which etymology justifies, and which is the most philosophical as well, nature should mean the principle of birth or genesis, the universal mother, the great cause, or system of causes, that brings phenomena to light. If we take the word nature in this sense, it may be said that Lucretius, more than any other man, is the poet of nature. Of course, being an ancient, he is not particularly a poet of landscape. He runs deeper than that; he is a poet of the source of landscape, a poet of matter. A poet of landscape might try to suggest, by well-chosen words, the sensations of light, movement, and form which nature arouses in us; but in this attempt he would encounter the insuperable difficulty which Lessing long ago pointed out, and warned poets of: I mean the unfitness of language to render what is spatial and material; its fitness to render only what, like language itself, is bodiless and flowing,--action, feeling, and thought. It is noticeable, accordingly, that poets who are fascinated by pure sense and seek to write poems about it are called not impressionists, but symbolists; for in trying to render some absolute sensation they render rather the field of association in which that sensation lies, or the emotions and half-thoughts that shoot and play about it in their fancy. They become--against their will, perhaps--psychological poets, ringers of mental chimes, and listeners for the chance overtones of consciousness. Hence we call them symbolists, mixing perhaps some shade of disparagement in the term, as if they were symbolists of an empty, super-subtle, or fatuous sort. For they play with things luxuriously, making them symbols for their thoughts, instead of mending their thoughts intelligently, to render them symbols for things.