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| Mirrors > Home > ILE Home > Th. List > dimatis | GIF version | ||
| Description: "Dimatis", one of the syllogisms of Aristotelian logic. Some 𝜑 is 𝜓, and all 𝜓 is 𝜒, therefore some 𝜒 is 𝜑. (In Aristotelian notation, IAI-4: PiM and MaS therefore SiP.) For example, "Some pets are rabbits.", "All rabbits have fur", therefore "Some fur bearing animals are pets". Like darii 2145 with positions interchanged. (Contributed by David A. Wheeler, 28-Aug-2016.) | 
| Ref | Expression | 
|---|---|
| dimatis.maj | ⊢ ∃𝑥(𝜑 ∧ 𝜓) | 
| dimatis.min | ⊢ ∀𝑥(𝜓 → 𝜒) | 
| Ref | Expression | 
|---|---|
| dimatis | ⊢ ∃𝑥(𝜒 ∧ 𝜑) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | dimatis.maj | . 2 ⊢ ∃𝑥(𝜑 ∧ 𝜓) | |
| 2 | dimatis.min | . . . . 5 ⊢ ∀𝑥(𝜓 → 𝜒) | |
| 3 | 2 | spi 1550 | . . . 4 ⊢ (𝜓 → 𝜒) | 
| 4 | 3 | adantl 277 | . . 3 ⊢ ((𝜑 ∧ 𝜓) → 𝜒) | 
| 5 | simpl 109 | . . 3 ⊢ ((𝜑 ∧ 𝜓) → 𝜑) | |
| 6 | 4, 5 | jca 306 | . 2 ⊢ ((𝜑 ∧ 𝜓) → (𝜒 ∧ 𝜑)) | 
| 7 | 1, 6 | eximii 1616 | 1 ⊢ ∃𝑥(𝜒 ∧ 𝜑) | 
| Colors of variables: wff set class | 
| Syntax hints: → wi 4 ∧ wa 104 ∀wal 1362 ∃wex 1506 | 
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 106 ax-ia2 107 ax-ia3 108 ax-5 1461 ax-gen 1463 ax-ie1 1507 ax-ie2 1508 ax-4 1524 ax-ial 1548 | 
| This theorem depends on definitions: df-bi 117 | 
| This theorem is referenced by: (None) | 
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