James Rush

He subsequently studied in Edinburgh, and, returning to Philadelphia, practised for several years, but afterward relinquished the active duties of his profession to devote himself to scientific and literary pursuits.

The main concept Rush wanted to establish was how the "voice must have distinct meanings or signs for declaring our thoughts and actions".

He argued that the thought of speech should be expanded into five separate sectors: vocality, time, pitch, force, and abruptness.

Rush also introduced the idea and concepts of phonemes, writing how there were thirty-five different speech sounds, and dividing these into three categories: tonic, subtonic, and atonic.

Following his wife's passing in 1857, Rush began work on his next most important piece of writing, Analysis of the Human Intellect.

[2] Rush coined the term mentivity as a definition towards how one thinks, and looked into how the brain functions as a physical embodiment of the mind and ones senses.

Rush's work in the Human Intellect is stated as one of the primary formations of the behavioristic school of psychology, as he targeted the motor system as a key towards one's behavior, including concepts such as personality, free association, and the effects of social aspects on one's psychology, all of which predated his peers in this field of work.