Diel was born in
Vienna,
Austria, on 11 July 1893, to a teacher of
German origin and an unknown man. He was
orphaned at the age of 13 after spending 8 years in a religious orphanage, but was able to obtain his
baccalauréat with the support of a benefactor. Diel did not pursue formal higher education, but instead became an actor, novelist, and poet before
teaching himself philosophy. Inspired by the philosophers
Plato,
Kant and
Spinoza, and also by the psychologists
Freud,
Adler and
Jung, he delved into his own psychological research and established the basis of the introspective analysis method that helped him develop his theories of the
psychology of motivation. Diel practiced psychotherapy at the central hospital of
Vienna, and in 1935 he sent his work on introspective analysis to
Albert Einstein. Einstein greatly appreciated Diel's work and they established a correspondence that did not end until Einstein's death in 1955. In 1938, after the
Nazi German Anschluss of
Austria, Diel escaped to
France and worked at the
Sainte-Anne psychiatric hospital in
Paris. Unfortunately, because he was a foreign national, he became imprisoned in the
Gurs internment camp in southern France during
World War II. After his release, he was able to join
CNRS in 1945 with the backing of Einstein and
Irène Joliot-Curie. At CNRS he worked as a children's psychotherapist in
Henri Wallon's laboratory. Diel continued working as a researcher and psychotherapist and had trained a group of students and published books on various subjects like
education,
symbolism and
evolution when he died of
cancer in Paris on 5 January 1972. ==Further reading==