Phenomenology and Heidegger

Phenomenology, the other great current shaping twentieth-century continental philosophy, begins with Edmund Husserl, who sought a rigorous, presuppositionless description of consciousness and its objects as they are actually experienced. Building on his teacher Franz Brentano's revival of the medieval notion of intentionality — the thesis that every mental act is directed at, or is 'of' or 'about,' some object, whether that object exists or not — Husserl made intentionality the central structure of consciousness. In the Logical Investigations (1900-1901) he distinguished the psychological act of experiencing from the ideal, shareable meanings or contents through which that act is directed at its object, arguing against psychologism, the reduction of logical and mathematical truths to merely contingent facts about human psychology, and insisting instead that meanings have an objective, ideal status independent of any particular thinker's mental states.