Mathbox for Richard Penner |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > MPE Home > Th. List > Mathboxes > frege5 | Structured version Visualization version GIF version |
Description: A closed form of syl 17. Identical to imim2 58. Theorem *2.05 of [WhiteheadRussell] p. 100. Proposition 5 of [Frege1879] p. 32. (Contributed by RP, 24-Dec-2019.) (Proof modification is discouraged.) |
Ref | Expression |
---|---|
frege5 | ⊢ ((𝜑 → 𝜓) → ((𝜒 → 𝜑) → (𝜒 → 𝜓))) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ax-frege1 40143 | . 2 ⊢ ((𝜑 → 𝜓) → (𝜒 → (𝜑 → 𝜓))) | |
2 | frege4 40152 | . 2 ⊢ (((𝜑 → 𝜓) → (𝜒 → (𝜑 → 𝜓))) → ((𝜑 → 𝜓) → ((𝜒 → 𝜑) → (𝜒 → 𝜓)))) | |
3 | 1, 2 | ax-mp 5 | 1 ⊢ ((𝜑 → 𝜓) → ((𝜒 → 𝜑) → (𝜒 → 𝜓))) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 |
This theorem was proved from axioms: ax-mp 5 ax-frege1 40143 ax-frege2 40144 |
This theorem is referenced by: rp-frege25 40158 frege6 40159 frege7 40161 frege9 40165 frege12 40166 frege16 40169 frege25 40170 frege18 40171 frege22 40172 frege14 40176 frege29 40184 frege34 40190 frege45 40202 frege80 40296 frege90 40306 |
Copyright terms: Public domain | W3C validator |