Nuprl Lemma : fo-logic-test1
∀x.(B x) ⇒ (C x) ⇒ ∃x.B x ⇒ ∃x.C x
Proof
Definitions occuring in Statement : 
language1: language1{i:l}(D,A,B,C,P,Q,R,H.fml[D;A;B;C;P;Q;R;H]), 
forsome: ∃x.P[x], 
forall: ∀x.P[x], 
implies: P ⇒ Q, 
apply: f a
Definitions unfolded in proof : 
language1: language1{i:l}(D,A,B,C,P,Q,R,H.fml[D;A;B;C;P;Q;R;H]), 
uall: ∀[x:A]. B[x], 
!hyp_hide: x, 
member: t ∈ T, 
prop: ℙ, 
implies: P ⇒ Q, 
so_lambda: λ2x.t[x], 
so_apply: x[s], 
forsome: ∃x.P[x], 
exists: ∃x:A. B[x], 
forall: ∀x.P[x], 
all: ∀x:A. B[x]
Lemmas referenced : 
forsome_wf, 
forall_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
sqequalHypSubstitution, 
functionEquality, 
cumulativity, 
hypothesisEquality, 
universeEquality, 
because_Cache, 
lambdaFormation, 
cut, 
lemma_by_obid, 
isectElimination, 
thin, 
sqequalRule, 
lambdaEquality, 
applyEquality, 
hypothesis, 
productElimination, 
addLevel, 
dependent_functionElimination, 
levelHypothesis, 
independent_functionElimination, 
dependent_pairFormation
Latex:
\mforall{}x.(B  x)  {}\mRightarrow{}  (C  x)  {}\mRightarrow{}  \mexists{}x.B  x  {}\mRightarrow{}  \mexists{}x.C  x
 Date html generated: 
2016_05_16-AM-09_07_56
 Last ObjectModification: 
2015_12_28-PM-07_03_18
Theory : first-order!and!ancestral!logic
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