Computer-assisted Proving by the PCS Method Bruno Buchberger In: Proceedings of the Workshop on Constructive Algebra (M. Hazewinkel, ed.), Amsterdam, Nov. 1-3, 2000. Lecture Notes in Computer Science, to appear, 14 pages ABSTRACT: Abstract: In this paper we describe Theorema, a system for supporting mathematical proving by computer. The emphasis of the paper is on showing how, in many situations, proving can be reduced to solving in algebraic domains. We first illustrate this by known techniques, in particular the Gröbner bases technique. Then we go into the details of describing the PCS technique, a new technique that is particularly well suited for doing proofs in elementary analysis and similar areas in which the notions involved, typically, contain alternating quantifiers in their definitions. We conclude with a general view on the interplay between automated proving, solving, and simplifying.