Husserl developed the phenomenological method to make possible “a descriptive account of the essential structures of the directly given.” Phenomenology emphasizes the immediacy of experience, the attempt to isolate it and set it off from all assumptions of existence or causal influence and lay bare its essential structure.

The basic method of all phenomenological investigation, as Husserl developed it himself—and on which he worked throughout his entire lifetime—is the “ reduction”: the existence of the world must be put between brackets, not because the philosopher should doubt it but merely because this existing world is not the very theme of phenomenology; its theme is rather the manner in which knowledge of the world comes about.