Theorem tr0 5212

Description: The empty set is transitive. (Contributed by NM, 16-Sep-1993.)

Assertion

Ref	Expression
tr0	⊢ Tr ∅

Proof of Theorem tr0

Step	Hyp	Ref	Expression
1		0ss 4349	. 2 ⊢ ∅ ⊆ 𝒫 ∅
2		dftr4 5206	. 2 ⊢ (Tr ∅ ↔ ∅ ⊆ 𝒫 ∅)
3	1, 2	mpbir 231	1 ⊢ Tr ∅

Syntax hints:   ⊆ wss 3898  ∅c0 4282  𝒫 cpw 4549  Tr wtr 5200

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1968  ax-7 2009  ax-8 2115  ax-9 2123  ax-ext 2705

This theorem depends on definitions:  df-bi 207  df-an 396  df-tru 1544  df-fal 1554  df-ex 1781  df-sb 2068  df-clab 2712  df-cleq 2725  df-clel 2808  df-ral 3049  df-v 3439  df-dif 3901  df-ss 3915  df-nul 4283  df-pw 4551  df-uni 4859  df-tr 5201

This theorem is referenced by:  ord0  6365  tctr  9635  tc0  9642  r1tr  9676