11. Contemporary research in set theory includes the study of large cardinals and determinacy. 12. The resulting axiom is now part of the standard axioms of set theory . 13. Research into higher-order computability theory demonstrated its connections to set theory . 14. It is important in effective descriptive set theory and recursion theory. 15. Classical descriptive set theory includes the study of regularity properties of Borel sets. 16. According to naive set theory , any definable collection is a set. 17. The development of classes mirrors the development of naive set theory . 18. Gamer has been credited with early contributions to diatonic set theory . 19. Robinson explored such areas as logic, set theory , complex analysis and number theory. 20. SierpiDski edited the journal, which specialized in papers on set theory .
