Note 387 — QUARRELS OF AUTHORS; (continued 4)

When all animosities had ceased, after the death of Hobbes, I find Dr. Wallis, in a very temperate letter to Tenison, exposing the errors of Hobbes in mathematical studies; Wallis acknowledges that philology had never entered into his pursuits,—in this he had never designed to oppose his superior genius: but it was Hobbes who had too often turned his mathematical into a philological controversy. Wallis has made a just observation on the nature of mathematical truths:—“Hobbes’s argumentations are destructive in one part of what is said in another. This is more convincingly evident, and more unpardonable, in mathematics than in other discourses, which are things capable of cogent demonstration, and so evident, that though a good mathematician may be subject to commit an error, yet one who understands but little of it cannot but see a fault when it is showed him.”

Wallis was an eminent genius in scientific pursuits. His art of decyphering letters was carried to amazing perfection; and among other phenomena he discovered was that of teaching a young man, born deaf and dumb, to speak plainly. He humorously observes, in one of his letters:—“I am now employed upon another work, as hard almost as to make Mr. Hobbes understand mathematics. It is to teach a person dumb and deaf to speak, and to understand a language.”