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Theorem rabid 2787
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 2623 . 2 {x A φ} = {x (x A φ)}
21abeq2i 2460 1 (x {x A φ} ↔ (x A φ))
Colors of variables: wff setvar class
Syntax hints:  wb 176   wa 358   wcel 1710  {crab 2618
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-3 7  ax-mp 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 2623
This theorem is referenced by:  rabeq2i  2856
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