Mordecai Kaplan

Mordecai Menahem Kaplan (; June 11, 1881 – November 8, 1983) was an American Conservative rabbi, writer, Jewish educator, professor, theologian-philosopher, activist, and religious leader who founded the Reconstructionist movement of Judaism with his son-in-law, Rabbi Ira Eisenstein. He has been described as a "towering figure" in the recent history of Judaism for his influential work in adapting it to modern society, contending that Judaism should be a unifying and creative force by stressing the cultural and historical character of the religion as well as theological doctrine. the son of Haya and Rabbi Israel Kaplan. Mordecai was brought over to New York in 1889, at the age of nine.

Career Kaplan was ordained at the Jewish Theological Seminary of America in 1902.

Not all of Kaplan's writings on the subject were consistent; his position evolved somewhat over the years, and two distinct theologies can be discerned with careful reading. The view more popularly associated with Kaplan is strict naturalism, à la John Dewey, which has been criticized as using religious terminology to mask a nontheistic (if not outright atheistic) position—one JTS colleague in the 1950s, Will Herberg, went so far as to compare it to the position of Charles Maurras toward the Catholic Church. A second strand of Kaplanian theology makes clear that God has ontological reality, a real and absolute existence independent of human beliefs, while rejecting classical theism and any belief in miracles. In 1973, he was one of the signers of the Humanist Manifesto II.

Personal life Kaplan was a prolific writer. In addition to his published works, he kept a journal from 1913 until the late 1970s, comprising 27 volumes, each with 350–400 handwritten pages. The journal is quite possibly the largest by a Jew, and may even be one of the most extensive on record.