Rapaport was born in Budapest, Hungary on September 30, 1911. A precocious student, he received Bachelor of Science degrees in mathematics and experimental physics in 1935, and a Ph.D. in psychology and philosophy in 1938, all attained at the Royal Hungarian Petrus Pazmany University in Budapest. During this period he also obtained a Montessori teaching degree. Beginning when Rapaport was a teenager, he participated in a Zionist organization and helped Hungarian Jews escape to Palestine. From 1932-1934, Rapaport lived on a kibbutz in Palestine, where he met and married Elvira Strasser and where his first child, Hanna, was born (Gill, 1961; Knight, 1961).