Naive Set Theory

• unlike axiomatic set theories (which are defined using formal logic) naive set theory is defined informally
• a set is described as a well-defined collection of objects

Bertrand Russel’s Paradox

• let 𝑅 be a set of sets that don’t contain itself
• if 𝑅 is not in set 𝑅 then 𝑅 belongs in set 𝑅 based on the definition of set 𝑅
• therefore contradiction

Zermelo-Fraenkel Set Theory

• TODO