Heidegger’s phenomenology from this period of his work can be described as existentialized transcendental philosophy—a brand of (clandestine or unorthodox) Kantianism that replaces the detached, formal investigations of the a priori conditions of experience to be found in Kant and his late-19th century neo-Kantian successors (chiefly Herman Cohen and Paul Natorp) with an exploration of the vital, subjectively experienced strata underlying those very abstract, transcendental conditions.