Gault, R. H., & Howard, D. T. (1925). Habit. In R. H. Gault & D. T. Howard, Outline of general psychology (pp. 61-80). New York, NY, US: Longmans, Green and Co.
http://dx.doi.org/10.1037/13428-004
Human nature has its constants and its variables. The term habit, as it is commonly used, has reference to the fixed--as contrasted with the variable--elements in man's behavior. Habitual acts are such as are performed alike again and again in the presence of the same stimuli, or which seem to spring from some established tendency in the individual's make-up. Habitual conduct, in a word, is conceived as the resultant of constant factors in human nature. We must add this qualification: habit is employed in its most exact sense to refer to learned, modes of response, as distinguished from those which are native or instinctive. (PsycINFO Database Record (c) 2016 APA, all rights reserved)