Metamath Proof Explorer |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > MPE Home > Th. List > eq0 | Structured version Visualization version GIF version |
Description: The empty set has no elements. Theorem 2 of [Suppes] p. 22. (Contributed by NM, 29-Aug-1993.) |
Ref | Expression |
---|---|
eq0 | ⊢ (𝐴 = ∅ ↔ ∀𝑥 ¬ 𝑥 ∈ 𝐴) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nfcv 2751 | . 2 ⊢ Ⅎ𝑥𝐴 | |
2 | 1 | eq0f 3884 | 1 ⊢ (𝐴 = ∅ ↔ ∀𝑥 ¬ 𝑥 ∈ 𝐴) |
Colors of variables: wff setvar class |
Syntax hints: ¬ wn 3 ↔ wb 195 ∀wal 1473 = wceq 1475 ∈ wcel 1977 ∅c0 3874 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1713 ax-4 1728 ax-5 1827 ax-6 1875 ax-7 1922 ax-10 2006 ax-11 2021 ax-12 2034 ax-13 2234 ax-ext 2590 |
This theorem depends on definitions: df-bi 196 df-or 384 df-an 385 df-tru 1478 df-ex 1696 df-nf 1701 df-sb 1868 df-clab 2597 df-cleq 2603 df-clel 2606 df-nfc 2740 df-v 3175 df-dif 3543 df-nul 3875 |
This theorem is referenced by: 0el 3895 ssdif0 3896 difin0ss 3900 inssdif0 3901 ralf0 4030 ralf0OLD 4031 disjiun 4573 0ex 4718 dm0 5260 reldm0 5264 cnv0 5454 uzwo 11627 fzouzdisj 12373 hashgt0elex 13050 hausdiag 21258 rnelfmlem 21566 wzel 31015 wzelOLD 31016 unblimceq0 31668 knoppndv 31695 bj-ab0 32094 bj-nel0 32128 bj-nul 32209 bj-nuliota 32210 bj-nuliotaALT 32211 nninfnub 32717 prtlem14 33177 stoweidlem44 38937 nrhmzr 41663 zrninitoringc 41863 |
Copyright terms: Public domain | W3C validator |