German idealism
Neo-Kantianism refers broadly to a revived type of philosophy along the lines of that laid down by Immanuel Kant in the 18th century, or more specifically by Schopenhauer's criticism of the Kantian philosophy in his work "The World as Will and Representation" (1818), as well as by other post-Kantian philosophers such as Jakob Friedrich Fries and Johann Friedrich Herbart. It has some more specific reference in later German philosophy.
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.