But this being able to write is not a matter of putting words and clauses together with correctness and elegance. That much the mere scholar generally understands, and it is because he thinks it sufficient that he fails. What is wanted is a quality of mind which is too often excluded from the specialist by his habit of thought. "A few years of journalism," said Mr. W.B. Yeats on one occasion, "is an invaluable discipline for the man of letters." No one is more fully alive to the defects of journalism than Mr. Yeats--its frequent looseness, prejudice, obviousness, and dissipation of interest. But, in spite of that, he saw that the good journalist's faculty of addressing himself directly to the subject in hand, of stating it clearly and in its essentials without waste of words, of so escaping his own particular mould of thought that he may be easily intelligible to a variety of minds, required a discipline and a broadening invaluable to the man who really has something to say. The specialist is inclined to lack the broad outlook of one who is interested in many things; he acquires a jargon of his own; his mind runs in the narrow channel to which that jargon corresponds; the language he uses becomes stilted and dead. There is no tonic in the truths he tries to proclaim, no relevance to the rest of knowledge. In other words, what he has to say may be scientifically valuable, but he fails to convey it to any but his fellow-specialists. Mr. Brander Matthews points out that the great students are those who have combined the Teutonic thoroughness with the French comprehensiveness and lucidity. Gibbon and Mommsen are the great examples to which he points. England surely has been very rich in writers thorough and lucid, but we may observe that they follow rather the eighteenth-century tradition, with its intelligible common sense, than the romantic or transcendental tradition, with its mysticism and obscurity. Locke, Berkeley, and Hume, the most lucid of philosophers, are scarcely easier to follow than John Stuart Mill, Huxley, and Leslie Stephen. But it is hardly necessary to enter a _caveat_ against supposing that lucidity of expression is precisely proportional to clearness of thought. The philosophy of Kant did not admit of the simple language of Hume, and T.H. Green and Mr. Bradley are not to be blamed if they are more difficult to understand than Sir Leslie Stephen.