Theorem snnz 3723

Description: The singleton of a set is not empty. (Contributed by NM, 10-Apr-1994.)

Hypothesis

Ref	Expression
snnz.1	|- A e. _V

Assertion

Ref	Expression
snnz	|- { A } =/= (/)

Proof of Theorem snnz

Step	Hyp	Ref	Expression
1		snnz.1	. 2 |- A e. _V
2		snnzg 3721	. 2 |- ( A e. _V -> { A } =/= (/) )
3	1, 2	ax-mp 5	1 |- { A } =/= (/)

Syntax hints:   e. wcel 2158   =/= wne 2357   _Vcvv 2749   (/)c0 3434   {csn 3604

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 615  ax-in2 616  ax-io 710  ax-5 1457  ax-7 1458  ax-gen 1459  ax-ie1 1503  ax-ie2 1504  ax-8 1514  ax-10 1515  ax-11 1516  ax-i12 1517  ax-bndl 1519  ax-4 1520  ax-17 1536  ax-i9 1540  ax-ial 1544  ax-i5r 1545  ax-ext 2169

This theorem depends on definitions:  df-bi 117  df-tru 1366  df-nf 1471  df-sb 1773  df-clab 2174  df-cleq 2180  df-clel 2183  df-nfc 2318  df-ne 2358  df-v 2751  df-dif 3143  df-nul 3435  df-sn 3610

This theorem is referenced by:  0nep0  4177  1n0  6447  ssfii  6987