Naive Descriptive Set Theory

These notes are meant as an introduction to descriptive set theory. The goal is to provide a propaedeutic tour through the basics of the subject that does not assume any background in Set Theory (well, almost no background). The material is based on some notes taken by Bjork at a course given by Foreman at UC Irvine, and extensively rewritten by Foreman with editing help from the students in a graduate course given in 2010 at the Hebrew University of Jerusalem. Originally intended as an appendix for the paper The conjugacy problem in ergodic theory, by Foreman, Rudolph and Weiss, the notes contain adequate background for the descriptive set theoretic portion of that paper and covers some additional topics, such as norms, useful for other applications in analysis. Most of the material is taken from the book Classical Descriptive Set Theory, by A. Kechris [1], as well as the lecture notes from D. Marker ([2]) that are on the web. The notes here are much less complete than either of those sources.