Database
CLASSICAL FIRST-ORDER LOGIC WITH EQUALITY
Other axiomatizations related to classical propositional calculus
Stoic logic non-modal portion (Chrysippus of Soli)
stoic4b
Metamath Proof Explorer
Description: Stoic logic Thema 4 version b. This is version b, which is with the
phrase "or both". See stoic4a for more information. (Contributed by David A. Wheeler , 17-Feb-2019)
Ref
Expression
Hypotheses
stoic4b.1
⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝜒 )
stoic4b.2
⊢ ( ( ( 𝜒 ∧ 𝜑 ∧ 𝜓 ) ∧ 𝜃 ) → 𝜏 )
Assertion
stoic4b
⊢ ( ( 𝜑 ∧ 𝜓 ∧ 𝜃 ) → 𝜏 )
Proof
Step
Hyp
Ref
Expression
1
stoic4b.1
⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝜒 )
2
stoic4b.2
⊢ ( ( ( 𝜒 ∧ 𝜑 ∧ 𝜓 ) ∧ 𝜃 ) → 𝜏 )
3
1
3adant3
⊢ ( ( 𝜑 ∧ 𝜓 ∧ 𝜃 ) → 𝜒 )
4
simp1
⊢ ( ( 𝜑 ∧ 𝜓 ∧ 𝜃 ) → 𝜑 )
5
simp2
⊢ ( ( 𝜑 ∧ 𝜓 ∧ 𝜃 ) → 𝜓 )
6
simp3
⊢ ( ( 𝜑 ∧ 𝜓 ∧ 𝜃 ) → 𝜃 )
7
3 4 5 6 2
syl31anc
⊢ ( ( 𝜑 ∧ 𝜓 ∧ 𝜃 ) → 𝜏 )