Reconstructionist Judaism is a Jewish movement that views Judaism as a progressively evolving civilization rather than a religion, based on concepts developed by Mordecai Kaplan (1881–1983). The movement originated as a semi-organized stream within Conservative Judaism and developed from the late 1920s to 1940s, before it seceded in 1955 and established a rabbinical college in 1967. Reconstructionist Judaism is recognized by some scholars as one of the five streams of Judaism alongside Orthodox, Conservative, Reform, and Humanistic.