Perspicuity is the offset of profound thoughts. [ Vauvenargues ]

The first requisite of style, not only in rhetoric, but in all compositions, is perspicuity. [ Whately ]

The three foundations of thought: Perspicuity, amplitude and justness. The three ornaments of thought: Clearness, correctness and novelty. [ Catherall ]

To write a genuine familiar or truly English style is to write as anyone would speak in common conversation, who had a thorough command and choice of words, or who could discourse with ease, force, and perspicuity, setting aside all pedantic and oratorical flourishes. [ Hazlitt ]

Some authors write nonsense in a clear style, and others sense in an obscure one; some can reason without being able to persuade, others can persuade without being able to reason; some dive so deep that they descend into darkness, and others soar so high that they give us no light; and some, in a vain attempt to be cutting and dry, give us only that which is cut and dried. We should labor, therefore, to treat with ease of things that are difficult; with familiarity, of things that are novel; and with perspicuity, of things that are profound. [ Colton ]