NFE Home New Foundations Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  NFE Home  >  Th. List  >  df-nfc Unicode version

Definition df-nfc 2478
Description: Define the not-free predicate for classes. This is read " is not free in ". Not-free means that the value of cannot affect the value of , e.g., any occurrence of in is effectively bound by a "for all" or something that expands to one (such as "there exists"). It is defined in terms of the not-free predicate df-nf 1545 for wffs; see that definition for more information. (Contributed by Mario Carneiro, 11-Aug-2016.)
Assertion
Ref Expression
df-nfc  F/_  F/
Distinct variable groups:   ,   ,
Allowed substitution hint:   ()

Detailed syntax breakdown of Definition df-nfc
StepHypRef Expression
1 vx . . 3
2 cA . . 3
31, 2wnfc 2476 . 2  F/_
4 vy . . . . . 6
54cv 1641 . . . . 5
65, 2wcel 1710 . . . 4
76, 1wnf 1544 . . 3  F/
87, 4wal 1540 . 2  F/
93, 8wb 176 1  F/_  F/
Colors of variables: wff setvar class
This definition is referenced by:  nfci  2479  nfcr  2481  nfcd  2484  nfceqi  2485  nfceqdf  2488  nfnfc1  2492  nfnfc  2495  drnfc1  2505  drnfc2  2506  dfnfc2  3909
  Copyright terms: Public domain W3C validator