Database
CLASSICAL FIRST-ORDER LOGIC WITH EQUALITY
Propositional calculus
Logical conjunction
imp44
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imp45
Metamath Proof Explorer
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Theorem
imp44
Description:
An importation inference.
(Contributed by
NM
, 26-Apr-1994)
Ref
Expression
Hypothesis
imp4.1
⊢
φ
→
ψ
→
χ
→
θ
→
τ
Assertion
imp44
⊢
φ
∧
ψ
∧
χ
∧
θ
→
τ
Proof
Step
Hyp
Ref
Expression
1
imp4.1
⊢
φ
→
ψ
→
χ
→
θ
→
τ
2
1
imp4c
⊢
φ
→
ψ
∧
χ
∧
θ
→
τ
3
2
imp
⊢
φ
∧
ψ
∧
χ
∧
θ
→
τ