instrumentalism
In`stru*men"tal*ism, n. (Philos.) Defn: The view that the sanction of truth is its utility, or that truth is genuine only in so far as it is a valuable instrument. -- In`stru*men"tal*ist, n. Instrumentalism views truth as simply the value belonging to certain ideas in so far as these ideas are biological functions of our organisms, and psychological functions whereby we direct our choices and attain our successes. Josiah Royce.