If you were to ask twenty intelligent people, "What is the Thames?" the answer due to you from each would be—"a river." And yet this would hardly be matter to satisfy your enquiring mind. You would more probably say, "What do you know of the Thames?" or, "Describe the Thames to me." This would bring you a great variety of opinions, many dissertations on geological and national history, many words in praise of beauty, many personal confessions. Here would be the revelation of many minds approaching a great subject in as many manners, confirming and contradicting each other, making on the whole some impression of cumulative judgment, giving you many clues to what might be called the truth, no one of them by itself coming near to anything like full knowledge, and the final word would inevitably be left unsaid.
The question, "What is poetry?" has been answered innumerable times, often by the subtlest and clearest minds, and as many times has it been answered differently. The answer in itself now makes a large and distinguished literature to which, full as it is of keen intelligence and even of constructive vision, we can return with unstaling pleasure. The very poets themselves, it is true, lending their wits to the debate, have left the answer incomplete, as it must—not in the least unhappily—always remain. And yet, if we consider the matter for a moment, we find that all this wisdom, prospering from Sidney's Apology until to-day, does not strictly attempt to answer the question that is put. It does not tell us singly what poetry is, but it speculates upon the cause and effect of poetry. It enquires into the impulse that moves the poet to creation and describes, as far as individual limitations will allow, the way in which the poet's work impresses the world. When Wordsworth says "poetry is the breath and finer spirit of all knowledge," he is, exactly, in one intuitive word, telling us how poetry comes into being, directing us with an inspired gesture to its source, and not strictly telling us what it is; and so Shelley tells us in his fiery eloquence of the divine functions of poetry. But poetry is, in its naked being and apart from its cause and effect, a certain use of words, and, remembering this simple fact, there has been one perfect and final answer to the question, "What is poetry?" It was Coleridge's: "Poetry—the best words in the best order."