Though his mathematization of the mind proved a dead end, it encouraged early experimentalists like Fechner to apply mathematics to the psyche. His interpretation of space had an important influence on Helmholtz’s empirical theory of vision, and on Natorp’s “logicization” of Kantian spatio-temporal intuition. Herbart’s arguments against psychological faculties were taken over by Wundt, and his notions of the limen and the “subconscious” were fundamental to Freud’s psychoanalytic theory. In philosophy, Herbart anticipated key ideas of Phenomenology, such as Brentano’s conception of mental phenomena, and his ideas of representational force, the limen, and reproduction all find positive endorsement and development in Husserl’s Phenomenology. Finally, recent scholarship in both psychology and philosophy is rediscovering Herbart. For example, Boudewijnse et al.  argue not only for the contemporary relevance of Herbart’s psycho-mechanics, but also that it is supported by experiment. And Beiser’s important contribution to the early history of neo-Kantianism reveals Herbart as a radical and important interpreter of Kant.