Watch on Soap2day. Filmmaker Pierre-Henry Salfati (Gainsbourg by Gainsbourg) offers an accessible and eloquent introduction to the life and ideas of Martin Buber, one of the most influential modern Jewish philosophers and a contemporary of Albert Einstein, Franz Kafka and Theodor Herzl. As an ardent Zionist, Buber’s vision for the Jewish state and its peaceful co­existence with its neighbours was one of humanism and socialism.