James Mark Baldwin, Dictionary of Philosophy and Psychology, Bd. 1 (London: Macmillan, 1901)

»the relation between two or more relatively independent things or systems of change which advance, hinder, limit, or otherwise affect one another, with reference both to body-mind relations and to interrelations between objects in the environment and between objects and the environment.«

@book{Baldwin.1901,
 year = {1901},
 title = {Dictionary of Philosophy and Psychology, Bd. 1},
 address = {London},
 publisher = {Macmillan},
 editor = {Baldwin, James Mark}
}