Theorem ontr 6477

Description: An ordinal number is a transitive class. (Contributed by NM, 11-Jun-1994.) Put in closed form. (Resised by BJ, 28-Dec-2024.)

Assertion

Ref	Expression
ontr	⊢ (𝐴 ∈ On → Tr 𝐴)

Proof of Theorem ontr

Step	Hyp	Ref	Expression
1		eloni 6375	. 2 ⊢ (𝐴 ∈ On → Ord 𝐴)
2		ordtr 6379	. 2 ⊢ (Ord 𝐴 → Tr 𝐴)
3	1, 2	syl 18	1 ⊢ (𝐴 ∈ On → Tr 𝐴)

This proof depends on syntax axioms:   → wi 4   ∈ wcel 2144  Tr wtr 5211  Ord word 6364  Oncon0 6365

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-8 2146  ax-9 2154  ax-ext 2732

This proof depends on definitions:  df-bi 210  df-an 402  df-tru 1572  df-ex 1812  df-sb 2099  df-clab 2739  df-cleq 2752  df-clel 2835  df-ral 3077  df-v 3452  df-ss 3897  df-uni 4867  df-tr 5212  df-po 5559  df-so 5560  df-fr 5604  df-we 5606  df-ord 6368  df-on 6369

This theorem is used by:  onunisuc  6478  onuninsuci  7855  hfuniOLD  9932  nmuladdss  37086  par2catid  50903