Theorem 3imp

Importation inference. (Contributed by NM, 8-Apr-1994.) (Proof shortened by Wolf Lammen, 20-Jun-2022.)

Hypothesis
3imp.1
\( \vdash \varphi \rightarrow \psi \rightarrow \chi \rightarrow \theta \)
Conclusion
\( \vdash \varphi \wedge \psi \wedge \chi \rightarrow \theta \)
Proof
3imp.1
imp31 _
3impa _