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Related theorems GIF version |
| Description: Double quantification with existential uniqueness and "at most one." |
| Ref | Expression |
|---|---|
| 2eumo | ⊢ (∃!x∃*yφ → ∃*x∃!yφ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | euimmo 1422 | . 2 ⊢ (∀x(∃!yφ → ∃*yφ) → (∃!x∃*yφ → ∃*x∃!yφ)) | |
| 2 | eumo 1413 | . 2 ⊢ (∃!yφ → ∃*yφ) | |
| 3 | 1, 2 | mpg 988 | 1 ⊢ (∃!x∃*yφ → ∃*x∃!yφ) |
| Colors of variables: wff set class |
| Syntax hints: → wi 3 ∃!weu 1382 ∃*wmo 1383 |
| This theorem was proved from axioms: ax-1 4 ax-2 5 ax-3 6 ax-mp 7 ax-7 964 ax-gen 965 ax-8 966 ax-10 968 ax-11 969 ax-12 970 ax-17 973 ax-4 975 ax-5o 977 ax-6o 980 ax-9o 1125 ax-10o 1142 ax-16 1212 ax-11o 1220 |
| This theorem depends on definitions: df-bi 147 df-or 224 df-an 225 df-ex 983 df-sb 1174 df-eu 1384 df-mo 1385 |