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Related theorems GIF version |
| Description: Existential uniqueness implies "at most one." |
| Ref | Expression |
|---|---|
| eumo | ⊢ (∃!xφ → ∃*xφ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | eu5 1402 | . 2 ⊢ (∃!xφ ↔ (∃xφ ⋀ ∃*xφ)) | |
| 2 | 1 | pm3.27bi 326 | 1 ⊢ (∃!xφ → ∃*xφ) |
| Colors of variables: wff set class |
| Syntax hints: → wi 3 ∃wex 977 ∃!weu 1373 ∃*wmo 1374 |
| This theorem is referenced by: eumoi 1405 euimmo 1413 moaneu 1423 eupick 1427 euor2 1430 2eumo 1435 2eu2 1443 2eu5 1446 moeq3 1912 euabex 2757 reuxfr 2894 dffun7 3526 zfrep6 3600 fnopabg 3601 dff2 3802 fnoprabg 3997 |
| This theorem was proved from axioms: ax-1 4 ax-2 5 ax-3 6 ax-mp 7 ax-7 959 ax-gen 960 ax-8 961 ax-10 963 ax-11 964 ax-12 965 ax-17 968 ax-4 970 ax-5o 972 ax-6o 975 ax-9o 1119 ax-10o 1136 ax-16 1206 ax-11o 1213 |
| This theorem depends on definitions: df-bi 147 df-or 224 df-an 225 df-ex 978 df-sb 1168 df-eu 1375 df-mo 1376 |