These various habits of thought, or habitual expressions of life, are all phases of the single life sequence of the individual; therefore a habit formed in response to a given stimulus will necessarily affect the character of the response made to other stimuli. A modification of human nature at any one point is a modification of human nature as a whole.

Thorstein Veblen, R.H. Tawney, John Maynard Keynes (ed. 1990)