As to languages, they are three in number: Greek, Latin, and the native tongue. Laying down some principles on style in general, he says: "If a correct understanding, according to Horace, be the first principle and source of writing well, it follows that style, which is nothing else than a certain manner of writing, has two parts; first, the intelligent thought or sentiment, properly conceived; secondly, the expression of the same; so that, as man himself is made up of soul and body, all style likewise consists of the underlying thought and the manner of its expression." Thought must be true, perspicuous, and adapted to the subject. To think truly or justly of things, there is required mental power and insight, which distinguishes what is really the gist of a subject-matter from what is only a deceptive appearance, or is superficial. Assistance is to be had for all this from the reading of good books, from accurate reflection and protracted thought, which does not merely skim over the subject, or touch it in a desultory way; again, from the analysis of parts, causes, adjuncts; finally, from the prudent judgment of others, or what is called criticism. As to the ways of acquiring proper diction, Jouvancy says: "I would have you avail yourself of books which treat of this matter, not so as to imagine all is done by thumbing them; you will gain much more by the plentiful reading of the best writers"; and again, "'abundance of diction,' _copia verborum_, will be easily acquired by reading much." It is by reading, writing, and imitating the best authors that a good style is formed; and only the best authors are to be read, "lest the odor of a foreign and vicious style cling to the mind, as to new vases."