Nuprl Lemma : deq_property
∀[T:Type]. ∀[d:EqDecider(T)]. ∀[x,y:T].  uiff(x = y ∈ T;↑(d x y))
Proof
Definitions occuring in Statement : 
deq: EqDecider(T)
, 
assert: ↑b
, 
uiff: uiff(P;Q)
, 
uall: ∀[x:A]. B[x]
, 
apply: f a
, 
universe: Type
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
deq: EqDecider(T)
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uiff: uiff(P;Q)
, 
and: P ∧ Q
, 
uimplies: b supposing a
, 
implies: P 
⇒ Q
, 
all: ∀x:A. B[x]
, 
sq_stable: SqStable(P)
, 
squash: ↓T
, 
prop: ℙ
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
iff: P 
⇐⇒ Q
, 
rev_implies: P 
⇐ Q
, 
guard: {T}
Lemmas referenced : 
iff_wf, 
all_wf, 
bool_wf, 
set_wf, 
equal_wf, 
assert_witness, 
decidable__assert, 
assert_wf, 
sq_stable_from_decidable
Rules used in proof : 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
sqequalTransitivity, 
computationStep, 
isect_memberFormation, 
introduction, 
cut, 
independent_pairFormation, 
setElimination, 
thin, 
rename, 
lemma_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
applyEquality, 
hypothesisEquality, 
hypothesis, 
independent_functionElimination, 
dependent_functionElimination, 
imageMemberEquality, 
baseClosed, 
imageElimination, 
productElimination, 
independent_pairEquality, 
isect_memberEquality, 
because_Cache, 
equalityTransitivity, 
equalitySymmetry, 
axiomEquality, 
functionEquality, 
lambdaEquality, 
universeEquality
Latex:
\mforall{}[T:Type].  \mforall{}[d:EqDecider(T)].  \mforall{}[x,y:T].    uiff(x  =  y;\muparrow{}(d  x  y))
Date html generated:
2016_05_14-AM-06_06_22
Last ObjectModification:
2016_01_14-PM-07_31_49
Theory : equality!deciders
Home
Index