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| Mirrors > Home > ILE Home > Th. List > celaront | GIF version | ||
| Description: "Celaront", one of the syllogisms of Aristotelian logic. No 𝜑 is 𝜓, all 𝜒 is 𝜑, and some 𝜒 exist, therefore some 𝜒 is not 𝜓. (In Aristotelian notation, EAO-1: MeP and SaM therefore SoP.) For example, given "No reptiles have fur", "All snakes are reptiles.", and "Snakes exist.", prove "Some snakes have no fur". Note the existence hypothesis. Example from https://en.wikipedia.org/wiki/Syllogism. (Contributed by David A. Wheeler, 27-Aug-2016.) (Revised by David A. Wheeler, 2-Sep-2016.) |
| Ref | Expression |
|---|---|
| celaront.maj | ⊢ ∀𝑥(𝜑 → ¬ 𝜓) |
| celaront.min | ⊢ ∀𝑥(𝜒 → 𝜑) |
| celaront.e | ⊢ ∃𝑥𝜒 |
| Ref | Expression |
|---|---|
| celaront | ⊢ ∃𝑥(𝜒 ∧ ¬ 𝜓) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | celaront.maj | . 2 ⊢ ∀𝑥(𝜑 → ¬ 𝜓) | |
| 2 | celaront.min | . 2 ⊢ ∀𝑥(𝜒 → 𝜑) | |
| 3 | celaront.e | . 2 ⊢ ∃𝑥𝜒 | |
| 4 | 1, 2, 3 | barbari 2189 | 1 ⊢ ∃𝑥(𝜒 ∧ ¬ 𝜓) |
| Colors of variables: wff set class |
| Syntax hints: ¬ wn 3 → wi 4 ∧ wa 104 ∀wal 1400 ∃wex 1545 |
| 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 1500 ax-gen 1502 ax-ie1 1546 ax-ie2 1547 ax-4 1563 ax-ial 1587 |
| This theorem depends on definitions: df-bi 117 |
| This theorem is referenced by: (None) |
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