![]() |
Intuitionistic Logic Explorer |
< Previous
Next >
Nearby theorems |
|
Mirrors > Home > ILE Home > Th. List > 0iin | GIF version |
Description: An empty indexed intersection is the universal class. (Contributed by NM, 20-Oct-2005.) |
Ref | Expression |
---|---|
0iin | ⊢ ∩ 𝑥 ∈ ∅ 𝐴 = V |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-iin 3891 | . 2 ⊢ ∩ 𝑥 ∈ ∅ 𝐴 = {𝑦 ∣ ∀𝑥 ∈ ∅ 𝑦 ∈ 𝐴} | |
2 | vex 2742 | . . . 4 ⊢ 𝑦 ∈ V | |
3 | ral0 3526 | . . . 4 ⊢ ∀𝑥 ∈ ∅ 𝑦 ∈ 𝐴 | |
4 | 2, 3 | 2th 174 | . . 3 ⊢ (𝑦 ∈ V ↔ ∀𝑥 ∈ ∅ 𝑦 ∈ 𝐴) |
5 | 4 | abbi2i 2292 | . 2 ⊢ V = {𝑦 ∣ ∀𝑥 ∈ ∅ 𝑦 ∈ 𝐴} |
6 | 1, 5 | eqtr4i 2201 | 1 ⊢ ∩ 𝑥 ∈ ∅ 𝐴 = V |
Colors of variables: wff set class |
Syntax hints: = wceq 1353 ∈ wcel 2148 {cab 2163 ∀wral 2455 Vcvv 2739 ∅c0 3424 ∩ ciin 3889 |
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-in1 614 ax-in2 615 ax-io 709 ax-5 1447 ax-7 1448 ax-gen 1449 ax-ie1 1493 ax-ie2 1494 ax-8 1504 ax-10 1505 ax-11 1506 ax-i12 1507 ax-bndl 1509 ax-4 1510 ax-17 1526 ax-i9 1530 ax-ial 1534 ax-i5r 1535 ax-ext 2159 |
This theorem depends on definitions: df-bi 117 df-tru 1356 df-nf 1461 df-sb 1763 df-clab 2164 df-cleq 2170 df-clel 2173 df-nfc 2308 df-ral 2460 df-v 2741 df-dif 3133 df-nul 3425 df-iin 3891 |
This theorem is referenced by: riin0 3960 iin0r 4171 |
Copyright terms: Public domain | W3C validator |