Theorem onsno 28156

Description: A surreal ordinal is a surreal. (Contributed by Scott Fenton, 18-Mar-2025.)

Assertion

Ref	Expression
onsno	⊢ (𝐴 ∈ Ons → 𝐴 ∈ No )

Proof of Theorem onsno

Step	Hyp	Ref	Expression
1		onssno 28155	. 2 ⊢ Ons ⊆ No
2	1	sseli 3942	1 ⊢ (𝐴 ∈ Ons → 𝐴 ∈ No )

Syntax hints:   → wi 4   ∈ wcel 2109   No csur 27551  On_scons 28152

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-ext 2701

This theorem depends on definitions:  df-bi 207  df-an 396  df-ex 1780  df-sb 2066  df-clab 2708  df-cleq 2721  df-clel 2803  df-rab 3406  df-ss 3931  df-ons 28153

This theorem is referenced by:  elons2  28159  sltonold  28162  onscutleft  28164  onscutlt  28165  onnolt  28167  onslt  28168  bdayon  28173  onaddscl  28174  onmulscl  28175  onsfi  28247