Theorem nlim0 4372

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 3413	. . 3 ⊢ ¬ ∅ ∈ ∅
2		simp2 988	. . 3 ⊢ ((Ord ∅ ∧ ∅ ∈ ∅ ∧ ∅ = ∪ ∅) → ∅ ∈ ∅)
3	1, 2	mto 652	. 2 ⊢ ¬ (Ord ∅ ∧ ∅ ∈ ∅ ∧ ∅ = ∪ ∅)
4		dflim2 4348	. 2 ⊢ (Lim ∅ ↔ (Ord ∅ ∧ ∅ ∈ ∅ ∧ ∅ = ∪ ∅))
5	3, 4	mtbir 661	1 ⊢ ¬ Lim ∅

Syntax hints:  ¬ wn 3   ∧ w3a 968   = wceq 1343   ∈ wcel 2136  ∅c0 3409  ∪ cuni 3789  Ord word 4340  Lim wlim 4342

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 604  ax-in2 605  ax-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-ext 2147

This theorem depends on definitions:  df-bi 116  df-3an 970  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-v 2728  df-dif 3118  df-nul 3410  df-ilim 4347

This theorem is referenced by: (None)