Émile Durkheim was a French sociologist who formally established the academic discipline of modern social science, and, with Karl Marx and Max Weber, is commonly cited as one of the principal architects of it. His seminal monograph, Suicide, pioneered modern social research and served to distinguish social science from psychology or political philosophy. 
"He became a thoroughly convinced rationalist-humanist, almost an atheist." - From Émile Durkheim: Critical Assessments of Leading Sociologists, Volume 2 (pp. 3) by W.S.F. Pickering.