by the end of the period the study of individual behavior within organizations underwent a rebirth few authors did more to popularize what was often referred to as the new industrial humanism than douglas M.McGregor his abstraction of the contending traditional and humanistic managerial philosophies evolved in to his now famous theory X and theory Y sets of assumptions like herbert simon before him McGregor pointed out the absurdity of maintaining universal principles of organizational arrangement while such laws principles or proverbs may be appropriate in a highly disciplined hierarchical organization such as an army they may become ineffective and even dysfunctional when applied to modern organizations-especially governmental organization where a lack of hierarchical discipline is frequently considered to be a valuable check against autocratic tendencies McGregor's 1957 article the human side of enterprise reprint here presented the main themes of his more famous 1960 book with the same title