The Journal of Symbolic Logic

Research Article

Son of George and V = L

William G. Fleissner 1

University of Pittsburgh, Pittsburgh, Pennsylvania 15260


This paper has three parts. In this first part, we formulate and prove from V = L a new combinatorial principle, ⋄++. In the second part, we discuss the topological problem which led to the formulation of ⋄++. Finally, we use ⋄++ to construct a space solving the topological problem.

(Received November 10 1980)

Key words and phrases

  • Diamond;
  • V = L ;
  • collectionwise normal


1   Partially supported by NSF Grant MCS 79-01848.