Theorem ndeqi-P7.21 846

Description: Natural Deduction: '=' Introduction Axiom.

Assertion

Ref	Expression
ndeqi-P7.21	⊢ 𝑡 = 𝑡

Proof of Theorem ndeqi-P7.21

Step	Hyp	Ref	Expression
1		eqref-P5 626	1 ⊢ 𝑡 = 𝑡

Syntax hints:   = wff-equals 6

This theorem was proved from axioms:  ax-L1 11  ax-L2 12  ax-L3 13  ax-MP 14  ax-GEN 15  ax-L4 16  ax-L5 17  ax-L6 18  ax-L7 19

This theorem depends on definitions:  df-bi-D2.1 107  df-and-D2.2 133  df-or-D2.3 145  df-true-D2.4 155  df-rcp-AND3 161  df-exists-D5.1 596

This theorem is referenced by:  axL6ex-P7  925  eqsym-P7  936