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Mathbox for Adhemar
Minimal implicational calculus
adh-minim-ax1
Metamath Proof Explorer
Description: Derivation of ax-1 from adh-minim and ax-mp . Carew Arthur Meredith
derived ax-1 inA single axiom of positive logic , The Journal of
Computing Systems, volume 1, issue 3, July 1953, pages 169--170. However,
here we follow the shortened derivation by Ivo Thomas,On Meredith's sole
positive axiom , Notre Dame Journal of Formal Logic, volume XV, number 3,
July 1974, page 477. Polish prefix notation: CpCqp . (Contributed by ADH , 10-Nov-2023) (Proof modification is discouraged.)
(New usage is discouraged.)
Proof
Step
Hyp
Ref
Expression
1
adh-minim-ax1-ax2-lem1
⊢ ( 𝜑 → ( ( 𝜓 → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) → ( 𝜓 → 𝜑 ) ) )
2
adh-minim-ax1-ax2-lem1
⊢ ( ( 𝜓 → 𝜑 ) → ( ( 𝜓 → ( ( 𝜂 → ( ( 𝜁 → ( 𝜓 → 𝜎 ) ) → ( 𝜁 → 𝜎 ) ) ) → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) ) → ( 𝜓 → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) ) )
3
adh-minim-ax1-ax2-lem3
⊢ ( ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → ( 𝜓 → 𝜑 ) ) → ( 𝜓 → ( ( 𝜂 → ( ( 𝜁 → ( 𝜓 → 𝜎 ) ) → ( 𝜁 → 𝜎 ) ) ) → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) ) )
4
adh-minim-ax1-ax2-lem4
⊢ ( ( ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → ( 𝜓 → 𝜑 ) ) → ( 𝜓 → ( ( 𝜂 → ( ( 𝜁 → ( 𝜓 → 𝜎 ) ) → ( 𝜁 → 𝜎 ) ) ) → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) ) ) → ( ( ( 𝜓 → 𝜑 ) → ( ( 𝜓 → ( ( 𝜂 → ( ( 𝜁 → ( 𝜓 → 𝜎 ) ) → ( 𝜁 → 𝜎 ) ) ) → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) ) → ( 𝜓 → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) ) ) → ( ( 𝜓 → 𝜑 ) → ( 𝜓 → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) ) ) )
5
3 4
ax-mp
⊢ ( ( ( 𝜓 → 𝜑 ) → ( ( 𝜓 → ( ( 𝜂 → ( ( 𝜁 → ( 𝜓 → 𝜎 ) ) → ( 𝜁 → 𝜎 ) ) ) → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) ) → ( 𝜓 → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) ) ) → ( ( 𝜓 → 𝜑 ) → ( 𝜓 → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) ) )
6
2 5
ax-mp
⊢ ( ( 𝜓 → 𝜑 ) → ( 𝜓 → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) )
7
adh-minim-ax1-ax2-lem4
⊢ ( ( ( 𝜓 → 𝜑 ) → ( 𝜓 → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) ) → ( ( 𝜑 → ( ( 𝜓 → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) → ( 𝜓 → 𝜑 ) ) ) → ( 𝜑 → ( 𝜓 → 𝜑 ) ) ) )
8
6 7
ax-mp
⊢ ( ( 𝜑 → ( ( 𝜓 → ( ( 𝜒 → ( ( 𝜃 → ( 𝜓 → 𝜏 ) ) → ( 𝜃 → 𝜏 ) ) ) → 𝜑 ) ) → ( 𝜓 → 𝜑 ) ) ) → ( 𝜑 → ( 𝜓 → 𝜑 ) ) )
9
1 8
ax-mp
⊢ ( 𝜑 → ( 𝜓 → 𝜑 ) )