嵌套前件聚合\and
theorem imp_nested_assemb_and (A B C: wff): $ (A \imp B \imp C) \imp A \and B \imp C $;
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | imp_tran | ((A \imp B \imp C) \imp \neg C \imp A \imp \neg B) \imp ((\neg C \imp A \imp \neg B) \imp \neg (A \imp \neg B) \imp C) \imp (A \imp B \imp C) \imp \neg (A \imp \neg B) \imp C |
|
| 2 | imp_tran | ((A \imp B \imp C) \imp A \imp \neg C \imp \neg B) \imp ((A \imp \neg C \imp \neg B) \imp \neg C \imp A \imp \neg B) \imp (A \imp B \imp C) \imp \neg C \imp A \imp \neg B |
|
| 3 | imp_introl_imp | ((B \imp C) \imp \neg C \imp \neg B) \imp (A \imp B \imp C) \imp A \imp \neg C \imp \neg B |
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| 4 | imp_introrev_neg | (B \imp C) \imp \neg C \imp \neg B |
|
| 5 | 3, 4 | ax_mp | (A \imp B \imp C) \imp A \imp \neg C \imp \neg B |
| 6 | 2, 5 | ax_mp | ((A \imp \neg C \imp \neg B) \imp \neg C \imp A \imp \neg B) \imp (A \imp B \imp C) \imp \neg C \imp A \imp \neg B |
| 7 | imp_imp_swapl | (A \imp \neg C \imp \neg B) \imp \neg C \imp A \imp \neg B |
|
| 8 | 6, 7 | ax_mp | (A \imp B \imp C) \imp \neg C \imp A \imp \neg B |
| 9 | 1, 8 | ax_mp | ((\neg C \imp A \imp \neg B) \imp \neg (A \imp \neg B) \imp C) \imp (A \imp B \imp C) \imp \neg (A \imp \neg B) \imp C |
| 10 | neg_imp_swap | (\neg C \imp A \imp \neg B) \imp \neg (A \imp \neg B) \imp C |
|
| 11 | 9, 10 | ax_mp | (A \imp B \imp C) \imp \neg (A \imp \neg B) \imp C |
| 12 | 11 | conv and | (A \imp B \imp C) \imp A \and B \imp C |