German philosophy
Neo-Kantianism refers broadly to the revival of the type of philosophy explained by Immanuel Kant and of the interpretations of Kant provided by post-Kantian philosophers such as Schopenhauer, Jakob Friedrich Fries and Johann Friedrich Herbart. Major figures in the neo-Kantian movement, which began around the 1860s, include Friedrich Albert Lange and Hermann Cohen.
Henri Bergson
The foundation of Henri Bergson's philosophy, his theory of Duration, he discovered when trying to improve the inadequacies of Herbert Spencer's philosophy. Bergson introduced Duration as a theory of time and consciousness in his doctoral thesis "Time and Free Will: An Essay on the Immediate Data of Consciousness" as a response to another of his influences: Immanuel Kant.