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Theorem axi9 2330
Description: Axiom of existence (intuitionistic logic axiom ax-i9). In classical logic, this is equivalent to ax-9 1654 but in intuitionistic logic it needs to be stated using the existential quantifier. (Contributed by Jim Kingdon, 31-Dec-2017.)
Assertion
Ref Expression
axi9 x x = y

Proof of Theorem axi9
StepHypRef Expression
1 a9e 1951 1 x x = y
Colors of variables: wff setvar class
Syntax hints:  wex 1541
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925
This theorem depends on definitions:  df-bi 177  df-an 360  df-tru 1319  df-ex 1542  df-nf 1545
This theorem is referenced by: (None)
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