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Theorem pm5.13dc 912
Description: An implication holds in at least one direction, where one proposition is decidable. Based on theorem *5.13 of [WhiteheadRussell] p. 123. (Contributed by Jim Kingdon, 30-Mar-2018.)
Assertion
Ref Expression
pm5.13dc (DECID 𝜓 → ((𝜑𝜓) ∨ (𝜓𝜑)))

Proof of Theorem pm5.13dc
StepHypRef Expression
1 pm5.14dc 911 1 (DECID 𝜓 → ((𝜑𝜓) ∨ (𝜓𝜑)))
Colors of variables: wff set class
Syntax hints:  wi 4  wo 708  DECID wdc 834
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in2 615  ax-io 709
This theorem depends on definitions:  df-bi 117  df-dc 835
This theorem is referenced by: (None)
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