MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  df-en Unicode version

Definition df-en 7274
Description: Define the equinumerosity relation. Definition of [Enderton] p. 129. We define to be a binary relation rather than a connective, so its arguments must be sets to be meaningful. This is acceptable because we do not consider equinumerosity for proper classes. We derive the usual definition as bren 7281. (Contributed by NM, 28-Mar-1998.)
Assertion
Ref Expression
df-en
Distinct variable group:   , ,

Detailed syntax breakdown of Definition df-en
StepHypRef Expression
1 cen 7270 . 2
2 vx . . . . . 6
32cv 1669 . . . . 5
4 vy . . . . . 6
54cv 1669 . . . . 5
6 vf . . . . . 6
76cv 1669 . . . . 5
83, 5, 7wf1o 5437 . . . 4
98, 6wex 1565 . . 3
109, 2, 4copab 4375 . 2
111, 10wceq 1670 1
Colors of variables: wff set class
This definition is referenced by:  relen  7278  bren  7281  enssdom  7296
  Copyright terms: Public domain W3C validator