[4] Watson's system was founded on that of Thomas Braidwood, with some developments and improvements.

[5] His book Instruction of the Deaf and Dumb describes his philosophy and his teaching methods.

He wrote, "Persons born deaf are, in fact, neither depressed below, nor raised above, the general scale of human nature, as regards their dispositions and powers, either of body or mind."

He was opposed to signed versions of spoken language, such as was used in a Paris school.

[2] The Abbé Sicard, the French teacher of the deaf, was much interested in his methods, and corresponded with him about the school.