First, he overthrew a
supposedly psychologistic position in the foundation of arithmetic, striving
instead to establish anti-psychologistic, objective foundations of logic and
mathematics.
Second, he moved from a
conception of philosophy as rooted in Brentanian descriptive psychology to the
development of a new discipline of "phenomenology" and a metaphysical
position dubbed "transcendental idealism".
And third, he transformed
this phenomenology, which initially amounted to a form of methodological solipsism,
into a phenomenology of intersubjectivity and ultimately (especially in
his Crisis 1936) into an ontology of the life-world, embracing
the social world and culture.
(The Cambridge Companion of
Husserl, ed. by Barry Smith, David Woodruff Smith, CUP, 1995, p. 11)
