NFE Home New Foundations Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  NFE Home  >  Th. List  >  rabid GIF version

Theorem rabid 2788
Description: An "identity" law of concretion for restricted abstraction. Special case of Definition 2.1 of [Quine] p. 16. (Contributed by NM, 9-Oct-2003.)
Assertion
Ref Expression
rabid (x {x A φ} ↔ (x A φ))

Proof of Theorem rabid
StepHypRef Expression
1 df-rab 2624 . 2 {x A φ} = {x (x A φ)}
21abeq2i 2461 1 (x {x A φ} ↔ (x A φ))
Colors of variables: wff setvar class
Syntax hints:  wb 176   wa 358   wcel 1710  {crab 2619
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-11 1746  ax-ext 2334
This theorem depends on definitions:  df-bi 177  df-an 360  df-ex 1542  df-sb 1649  df-clab 2340  df-cleq 2346  df-clel 2349  df-rab 2624
This theorem is referenced by:  rabeq2i  2857
  Copyright terms: Public domain W3C validator