Axiomatic Set Theory: Problem sheet[removed]a) Assuming ZF (ie. ZF∗ +Foundation) prove that the following two definitions of “ordinal” are equivalent: (i) An ordinal is a transitive set well-ordered by ∈. (ii) An o

Source URL: people.maths.ox.ac.uk

• Ordinal numbers
• Axioms of set theory
• Z notation
• Constructible universe
• Ordinal arithmetic
• Axiom of regularity
• S
• Hartogs number
• Reflection principle
• Mathematical logic
• Mathematics
• Set theory