W. I. Thomas

American [[sociologist]] and [[educator]] William Isaac Thomas (August 13, 1863 – December 5, 1947) was an American sociologist. With the help of Polish sociologist Florian Znaniecki, W.I. Thomas developed and influenced the use of empirical methodologies in sociological research and contributed theories to the sociology of migration. Thomas then went on to formulate a fundamental principle of sociology, known as the Thomas theorem (also known as the Thomas dictum). Through his theorem, Thomas contended that, "If men define situations as real, they are real in their consequences". This microsociological concept served as a theoretical foundation for the field of symbolic interactionism which was developed by Thomas's younger peers - primarily at the University of Chicago. Provided by Wikipedia

1
by Thomas, William Isaac
Published 1958
Dover Publications

2
by Thomas, William Isaac
Published 1907
University of Chicago press; [etc., etc.]