Theorem com24

Commutation of antecedents. Swap 2nd and 4th. Deduction associated with com13. (Contributed by NM, 25-Apr-1994.) (Proof shortened by Wolf Lammen, 28-Jul-2012.)

Hypothesis

com4.1

\( \vdash \varphi \rightarrow \psi \rightarrow \chi \rightarrow \theta \rightarrow \tau \)

Conclusion

\( \vdash \varphi \rightarrow \theta \rightarrow \chi \rightarrow \psi \rightarrow \tau \)

Proof

com4.1

com4t _

com13 _