Nuprl Lemma : mFOL-proveable-evidence
Soundness theorem for mFOL() with respect to uniform evidence semantics.
It says that from a correct proof of a mFOL sequent we may construct
uniform evidence mFOL-sequent-evidence for the sequent.
Uniform evidence for an abstract formula, fmla, is the 
intersection over all domains, Dom, and all structures, S, over Dom,
of evidence for ∀a:FOAssignment(Dom). Dom,S,a |= fmla.
NOTE:
Since there are no assignments into an empty domain, this means that any
evidence works when Dom is empty, so the intersection is essentially over
non-empty domains Dom. 
Thus, (forall x. P(x)) => (exists x. P(x)) is uniformly valid
(i.e. has uniform evidence) so (by our completeness theorem) is provable.
A careful examination of the effect of the mFOL rules 
 (see mFOLeffect)
will show that it is indeed provable.⋅
∀[s:mFOL-sequent()]. (mFOL-proveable(s) 
⇒ mFOL-sequent-evidence(s))
Proof
Definitions occuring in Statement : 
mFOL-proveable: mFOL-proveable(s)
, 
mFOL-sequent-evidence: mFOL-sequent-evidence(s)
, 
mFOL-sequent: mFOL-sequent()
, 
uall: ∀[x:A]. B[x]
, 
implies: P 
⇒ Q
Lemmas : 
mFOL-proveable_wf, 
mFOL-sequent_wf, 
W-induction, 
mFOLRule_wf, 
mFOLeffect_wf, 
list_wf, 
unit_wf2, 
int_seg_wf, 
length_wf, 
all_wf, 
correct_proof_wf, 
subtype_rel_self, 
proof-tree_wf, 
mFOL-sequent-evidence_wf, 
W_wf, 
mFOLRule-induction, 
mFOL_wf, 
mFOconnect?_wf, 
bool_wf, 
eqtt_to_assert, 
eq_atom_wf, 
mFOconnect-knd_wf, 
assert_of_eq_atom, 
length_of_cons_lemma, 
length_of_nil_lemma, 
less_than_wf, 
false_wf, 
lelt_wf, 
select_wf, 
equal_wf, 
list-cases, 
cons_neq_nil, 
mFOconnect-left_wf, 
cons_wf, 
mFOconnect-right_wf, 
product_subtype_list, 
length_wf_nat, 
nat_wf, 
decidable__lt, 
condition-implies-le, 
minus-add, 
minus-one-mul, 
zero-add, 
add-commutes, 
add_functionality_wrt_le, 
add-associates, 
add-zero, 
le-add-cancel, 
length_nil, 
non_neg_length, 
nil_wf, 
length_wf_nil, 
length_cons, 
eqff_to_assert, 
bool_cases_sqequal, 
subtype_base_sq, 
bool_subtype_base, 
assert-bnot, 
neg_assert_of_eq_atom, 
bfalse_wf, 
and_wf, 
isl_wf, 
btrue_wf, 
btrue_neq_bfalse, 
equal-wf-base-T, 
mRuleandI_wf, 
mRuleimpI_wf, 
bl-all_wf, 
l_member_wf, 
bnot_wf, 
deq-member_wf, 
int-deq_wf, 
mFOL-freevars_wf, 
iff_transitivity, 
assert_wf, 
l_all_wf2, 
not_wf, 
iff_weakening_uiff, 
assert-bl-all, 
l_all_functionality, 
assert_of_bnot, 
assert-deq-member, 
eq_bool_wf, 
mFOquant-isall_wf, 
assert_of_eq_bool, 
mFOL-subst_wf, 
mFOquant-body_wf, 
mFOquant-var_wf, 
equal-wf-T-base, 
mRuleallI_wf, 
mFOquant?_wf, 
mRuleexistsI_wf, 
mRuleorI_wf, 
deq-mFO_wf, 
mRulehyp_wf, 
lt_int_wf, 
assert_of_lt_int, 
null_nil_lemma, 
null_wf3, 
subtype_rel_list, 
top_wf, 
null_cons_lemma, 
sq_stable__le, 
mRuleandE_wf, 
mRuleorE_wf, 
mRuleimpE_wf, 
mRuleallE_wf, 
mRuleexistsE_wf, 
mFOL-induction, 
mFOconnect_wf, 
squash_wf, 
true_wf, 
iff_weakening_equal, 
equal-wf-base, 
atom_subtype_base, 
mFOL-sequent-evidence_and, 
map_cons_lemma, 
tupletype_cons_lemma, 
FOAssignment_wf, 
FOStruct_wf, 
map_nil_lemma, 
tupletype_nil_lemma, 
FOSatWith_wf, 
mFOL-abstract_wf, 
map_wf, 
assert_of_null, 
tuple-type_wf, 
mFOquant_wf, 
mFOatomic_wf, 
mFOL-subst-abstract, 
update-assignment_wf, 
eq_int_wf, 
assert_of_eq_int, 
neg_assert_of_eq_int, 
mFOL-abstract-functionality, 
member_filter, 
int_subtype_base, 
list_induction, 
l_all_cons, 
mFOL-sequent-evidence_transitivity1, 
mFOL-sequent-evidence-trivial, 
mFOL-sequent-evidence_transitivity2, 
select-cons, 
le_int_wf, 
le_wf, 
add-swap, 
decidable__le, 
subtract_wf, 
not-le-2, 
minus-minus, 
minus-zero, 
le-add-cancel2, 
less_than_transitivity2, 
le_weakening, 
bool_cases, 
assert_of_le_int, 
select-tuple_wf, 
map_length, 
select-map, 
stuck-spread, 
base_wf, 
null-map, 
less_than_transitivity1, 
less_than_irreflexivity, 
sq_stable__correct_proof, 
proof-tree-ext
\mforall{}[s:mFOL-sequent()].  (mFOL-proveable(s)  {}\mRightarrow{}  mFOL-sequent-evidence(s))
Date html generated:
2015_07_17-AM-07_57_12
Last ObjectModification:
2015_02_03-PM-09_43_19
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