Nuprl Lemma : un-half-squash-test
∀[P,Q,R:ℙ].  (((P ∧ R) 
⇒ Q) 
⇒ ⇃(R) 
⇒ half-squash-stable(Q) 
⇒ ⇃(P) 
⇒ True 
⇒ {Q ∧ ⇃(P) ∧ (∀n:ℕ. Q)})
Proof
Definitions occuring in Statement : 
half-squash-stable: half-squash-stable(P)
, 
quotient: x,y:A//B[x; y]
, 
nat: ℕ
, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
guard: {T}
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
and: P ∧ Q
, 
true: True
Definitions unfolded in proof : 
cand: A c∧ B
, 
half-squash-stable: half-squash-stable(P)
, 
all: ∀x:A. B[x]
, 
so_apply: x[s]
, 
so_lambda: λ2x.t[x]
, 
uimplies: b supposing a
, 
so_apply: x[s1;s2]
, 
so_lambda: λ2x y.t[x; y]
, 
and: P ∧ Q
, 
prop: ℙ
, 
member: t ∈ T
, 
guard: {T}
, 
implies: P 
⇒ Q
, 
uall: ∀[x:A]. B[x]
Lemmas referenced : 
trivial-quotient-true, 
half-squash-stable_wf, 
implies-quotient-true, 
half-squash-stable__all, 
half-squash-stable__half-squash, 
nat_wf, 
all_wf, 
equiv_rel_true, 
true_wf, 
quotient_wf, 
half-squash-stable__and
Rules used in proof : 
independent_pairFormation, 
universeEquality, 
functionEquality, 
promote_hyp, 
cumulativity, 
independent_functionElimination, 
independent_isectElimination, 
hypothesis, 
lambdaEquality, 
because_Cache, 
productEquality, 
hypothesisEquality, 
thin, 
isectElimination, 
sqequalHypSubstitution, 
extract_by_obid, 
introduction, 
sqequalRule, 
cut, 
lambdaFormation, 
isect_memberFormation, 
sqequalReflexivity, 
computationStep, 
sqequalTransitivity, 
sqequalSubstitution
Latex:
\mforall{}[P,Q,R:\mBbbP{}].
    (((P  \mwedge{}  R)  {}\mRightarrow{}  Q)  {}\mRightarrow{}  \00D9(R)  {}\mRightarrow{}  half-squash-stable(Q)  {}\mRightarrow{}  \00D9(P)  {}\mRightarrow{}  True  {}\mRightarrow{}  \{Q  \mwedge{}  \00D9(P)  \mwedge{}  (\mforall{}n:\mBbbN{}.  Q)\})
Date html generated:
2017_09_29-PM-05_48_13
Last ObjectModification:
2017_08_30-AM-11_48_12
Theory : quot_1
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