Def Refl(T;x,y.E(x;y)) == a:T. E(a;a)

is mentioned by

Thm* R,R':(TTProp). Thm* (x,y:T. R(x,y)  R'(x,y))  (Refl(T;x,y.R(x,y))  Refl(T;x,y.R'(x,y)))	[refl_functionality_wrt_iff]
Def Order(T;x,y.R(x;y)) Def == Refl(T;x,y.R(x;y)) & (Trans x,y:T. R(x;y)) & AntiSym(T;x,y.R(x;y))	[order]
Def Preorder(T;x,y.R(x;y)) == Refl(T;x,y.R(x;y)) & (Trans x,y:T. R(x;y))	[preorder]
Def EquivRel x,y:T. E(x;y) Def == Refl(T;x,y.E(x;y)) & (Sym x,y:T. E(x;y)) & (Trans x,y:T. E(x;y))	[equiv_rel]

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