Theorem tru 1399

Description: The truth value ⊤ is provable. (Contributed by Anthony Hart, 13-Oct-2010.)

Assertion

Ref	Expression
tru	⊢ ⊤

Proof of Theorem tru

Step	Hyp	Ref	Expression
1		id 19	. 2 ⊢ (∀𝑥 𝑥 = 𝑥 → ∀𝑥 𝑥 = 𝑥)
2		df-tru 1398	. 2 ⊢ (⊤ ↔ (∀𝑥 𝑥 = 𝑥 → ∀𝑥 𝑥 = 𝑥))
3	1, 2	mpbir 146	1 ⊢ ⊤

Syntax hints:   → wi 4  ∀wal 1393   = wceq 1395  ⊤wtru 1396

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108

This theorem depends on definitions:  df-bi 117  df-tru 1398

This theorem is referenced by:  fal  1402  dftru2  1403  mptru  1404  tbtru  1405  bitru  1407  trud  1411  truan  1412  truorfal  1448  falortru  1449  truimfal  1452  nftru  1512  euotd  4340  rabxfr  4560  reuhyp  4562  elabrex  5880  elabrexg  5881  caovcl  6159  caovass  6165  caovdi  6184  ectocl  6747  reef11  12205  mpomulcn  15234  bj-sbimeh  16094  bdtru  16153  bj-nn0suc0  16271