Theorem nlim0 4393

Description: The empty set is not a limit ordinal. (Contributed by NM, 24-Mar-1995.) (Proof shortened by Andrew Salmon, 25-Jul-2011.)

Assertion

Ref	Expression
nlim0	⊢ ¬ Lim ∅

Proof of Theorem nlim0

Step	Hyp	Ref	Expression
1		noel 3426	. . 3 ⊢ ¬ ∅ ∈ ∅
2		simp2 998	. . 3 ⊢ ((Ord ∅ ∧ ∅ ∈ ∅ ∧ ∅ = ∪ ∅) → ∅ ∈ ∅)
3	1, 2	mto 662	. 2 ⊢ ¬ (Ord ∅ ∧ ∅ ∈ ∅ ∧ ∅ = ∪ ∅)
4		dflim2 4369	. 2 ⊢ (Lim ∅ ↔ (Ord ∅ ∧ ∅ ∈ ∅ ∧ ∅ = ∪ ∅))
5	3, 4	mtbir 671	1 ⊢ ¬ Lim ∅

Syntax hints:  ¬ wn 3   ∧ w3a 978   = wceq 1353   ∈ wcel 2148  ∅c0 3422  ∪ cuni 3809  Ord word 4361  Lim wlim 4363

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-3an 980  df-tru 1356  df-nf 1461  df-sb 1763  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-v 2739  df-dif 3131  df-nul 3423  df-ilim 4368

This theorem is referenced by: (None)