Logic Colloquium '90

This volume is the Proceedings of Logic Colloquium 90 held
in Helsinki, Finland, from July 15 to July 22, 1990.
The congress belongs to the annual series of the European
Summer Meetings of the Association for Symbolic Logic.
These proceedings contain 13 research papers written mainly
by the invited speakers of the congress. They represent all
fields of mathematical logic from the philosophy of
mathematics through model theory, proof theory, recursion
theory and set theory, to connections of logic to computer
science.