The works that Husserl published during his lifetime, and in the light of which one is accustomed to write one's account of the development of his thought, are but the tips of an iceberg. By far the larger parts of his work remained as unpublished manuscripts. Now that some of these manuscripts have been published, it is possible to reconstruct a more accurate account of the development of his thought than was possible some years ago.

There is a well-known account of Husserl’s thought which, in simple outlines, runs as follows: a psychologistic Philosophy of Arithmetic (1891), written under the influence of Brentano and Stumpf, was rejected and superseded, largely owing to Frege’s severe criticism of that work; this was followed by an anti-psychologistic and realistic philosophy of logic in two volumes of the Logical Investigations (1900-01), which influenced the early Munich school that then gathered around Husserl in Gottingen. However, the Logical Investigations, according to this account, already showed interest in analysis of consciousness and presupposed a conception of phenomenology as a psychology whose task is to describe the essential structures of mental life. Thus the anti-psychologism of the Prolegomena quickly yielded to an overwhelming concern with the life of consciousness as the source of meanings - a concern that found its expression more than a decade later in Ideas pertaining to a Pure Phenomenology and Phenemenological Philosophy Book 1(1913).