ITERATED PRIORITY ARGUMENTS IN DESCRIPTIVE SET THEORY
Adam R. Day, Noam Greenberg, Matthew Harrison‐Trainor, Dan Turetsky · Bulletin of Symbolic Logic · 2024
Abstract We present the true stages machinery and illustrate its applications to descriptive set theory. We use this machinery to provide new proofs of the Hausdorff–Kuratowski and Wadge theorems on the structure of $\mathbf {\Delta }^0_\xi $ , Louveau and Saint Raymond’s separation theorem, and Louveau’s separation theorem.