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Theorem nannot 1293
Description: Show equivalence between negation and the Nicod version. To derive nic-dfneg 1435, apply nanbi 1294. (Contributed by Jeff Hoffman, 19-Nov-2007.)
Assertion
Ref Expression
nannot ψ ↔ (ψ ψ))

Proof of Theorem nannot
StepHypRef Expression
1 df-nan 1288 . . 3 ((ψ ψ) ↔ ¬ (ψ ψ))
2 anidm 625 . . 3 ((ψ ψ) ↔ ψ)
31, 2xchbinx 301 . 2 ((ψ ψ) ↔ ¬ ψ)
43bicomi 193 1 ψ ↔ (ψ ψ))
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wb 176   wa 358   wnan 1287
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8
This theorem depends on definitions:  df-bi 177  df-an 360  df-nan 1288
This theorem is referenced by:  nanbi  1294  trunantru  1354  falnanfal  1357  nic-dfneg  1435
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