DefInductiveClass (3.55, Definition): “Is successor-inductive (Peano-inductive)” predicate

Standalone kernel entity record from 3. Set/Class-Theoretic Foundations (3.01–3.78) — View in Complete Entity Database (#DefInductiveClass) →

Formula Display:
Proof Trees:

DefInductiveClass (3.55) — “Is successor-inductive (Peano-inductive)” predicate

Morse-Kelley / Von Neumann-Bernays-Gödel class comprehension, sethood, ordinals, Dunaev pairs, cardinals, universes, and reflection.

Num Entity Database Record (Vertical Field Table)
3.55
Title “Is successor-inductive (Peano-inductive)” predicate #DefInductiveClass #label-is-successor-inductive-peano-inductive-predicate
Classification Definition
Formula
0\(\href{../symbols/delimiters-brackets.html}{(} \href{../symbols/forall-binder.html}{\forall} \href{../symbols/delimiters-brackets.html}{(} \href{../symbols/variables.html}{X} \href{../symbols/typing-colon.html}{:} \href{../symbols/class-type.html}{\mathsf{Class}} \href{../symbols/delimiters-brackets.html}{)} \href{../symbols/delimiters-brackets.html}{(} \href{../symbols/ind-pred.html}{\mathrm{Ind}} \href{../symbols/delimiters-brackets.html}{(} \href{../symbols/variables.html}{X} \href{../symbols/delimiters-brackets.html}{)} \href{../symbols/iff-conn.html}{\longleftrightarrow} \href{../symbols/delimiters-brackets.html}{(} \href{../symbols/delimiters-brackets.html}{(} \href{../symbols/emptyset-const.html}{\emptyset} \href{../symbols/in-pred.html}{\in} \href{../symbols/variables.html}{X} \href{../symbols/delimiters-brackets.html}{)} \href{../symbols/and-conn.html}{\land} \href{../symbols/forall-binder.html}{\forall} \href{../symbols/delimiters-brackets.html}{(} \href{../symbols/variables.html}{a} \href{../symbols/typing-colon.html}{:} \href{../symbols/class-type.html}{\mathsf{Class}} \href{../symbols/delimiters-brackets.html}{)} \href{../symbols/delimiters-brackets.html}{(} \href{../symbols/delimiters-brackets.html}{(} \href{../symbols/variables.html}{a} \href{../symbols/in-pred.html}{\in} \href{../symbols/variables.html}{X} \href{../symbols/delimiters-brackets.html}{)} \href{../symbols/impl-conn.html}{\rightarrow} \href{../symbols/delimiters-brackets.html}{(} \href{../symbols/delimiters-brackets.html}{(} \href{../symbols/variables.html}{a} \href{../symbols/binunion-op.html}{\cup} \href{../symbols/singleton-op.html}{\{} \href{../symbols/variables.html}{a} \href{../symbols/singleton-op.html}{\}} \href{../symbols/delimiters-brackets.html}{)} \href{../symbols/in-pred.html}{\in} \href{../symbols/variables.html}{X} \href{../symbols/delimiters-brackets.html}{)} \href{../symbols/delimiters-brackets.html}{)} \href{../symbols/delimiters-brackets.html}{)} \href{../symbols/delimiters-brackets.html}{)} \href{../symbols/delimiters-brackets.html}{)} \)
SML Kernel AST TpInd
Scheme of Types 0(∀([X@Variable]:[Class@Type])(Ind([X@Class.Expression])⟷((∅∈[X@Class.Expression])∧∀([a@Variable]:[Class@Type])(([a@Class.Expression]∈[X@Class.Expression])→(([a@Class.Expression]∪{[a@Class.Expression]})∈[X@Class.Expression])))))
Kernel Note Successor-inductive (Peano 0-successor-inductive) in the narrowest sense: closed under 0 = ∅ and ordinal successor a |-> a ∪ {a}, as distinguished from transfinite ∈-induction (3.70) or 𝒫-induction.
Verification Definitional (Kernel AST) · Standalone Entry (DefInductiveClass) → · (3.55) · #DefInductiveClass