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Metamath Proof Explorer

Theorem sbtru

Description: The result of substituting in the truth constant "true" is true. (Contributed by BJ, 2-Sep-2023)

Ref Expression
Assertion sbtru 
|- [ y / x ] T.

Proof

Step Hyp Ref Expression
1 tru 
 |-  T.
2 1 sbt 
 |-  [ y / x ] T.