Nuprl Lemma : transitive-closure-symmetric
∀[A:Type]. ∀[R:A ⟶ A ⟶ ℙ].  (Sym(A;x,y.R x y) 
⇒ Sym(A;x,y.x TC(R) y))
Proof
Definitions occuring in Statement : 
transitive-closure: TC(R)
, 
sym: Sym(T;x,y.E[x; y])
, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
infix_ap: x f y
, 
implies: P 
⇒ Q
, 
apply: f a
, 
function: x:A ⟶ B[x]
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
implies: P 
⇒ Q
, 
sym: Sym(T;x,y.E[x; y])
, 
all: ∀x:A. B[x]
, 
infix_ap: x f y
, 
transitive-closure: TC(R)
, 
member: t ∈ T
, 
subtype_rel: A ⊆r B
, 
prop: ℙ
, 
so_lambda: λ2x y.t[x; y]
, 
so_apply: x[s1;s2]
, 
spreadn: spread3, 
and: P ∧ Q
, 
uimplies: b supposing a
, 
cand: A c∧ B
, 
top: Top
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
rel_path: rel_path(A;L;x;y)
, 
so_lambda: so_lambda(x,y,z.t[x; y; z])
, 
so_apply: x[s1;s2;s3]
, 
pi1: fst(t)
, 
pi2: snd(t)
, 
squash: ↓T
, 
true: True
, 
guard: {T}
Lemmas referenced : 
transitive-closure_wf, 
subtype_rel_self, 
istype-universe, 
sym_wf, 
subtype_rel_function, 
map_wf, 
reverse_wf, 
map-length, 
istype-void, 
length-reverse, 
rel_path_wf, 
less_than_wf, 
length_wf, 
list_induction, 
all_wf, 
list_wf, 
list_ind_nil_lemma, 
reverse_nil_lemma, 
map_nil_lemma, 
list_ind_cons_lemma, 
reverse-cons, 
map_append_sq, 
map_cons_lemma, 
cons_wf, 
squash_wf, 
true_wf, 
nil_wf, 
append_wf, 
rel_path-append, 
subtype_rel-equal
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
Error :isect_memberFormation_alt, 
Error :lambdaFormation_alt, 
sqequalHypSubstitution, 
rename, 
sqequalRule, 
Error :universeIsType, 
cut, 
applyEquality, 
introduction, 
extract_by_obid, 
isectElimination, 
thin, 
hypothesisEquality, 
hypothesis, 
instantiate, 
universeEquality, 
Error :inhabitedIsType, 
Error :lambdaEquality_alt, 
Error :functionIsType, 
setElimination, 
productElimination, 
Error :dependent_pairEquality_alt, 
functionExtensionality, 
because_Cache, 
functionEquality, 
independent_isectElimination, 
Error :productIsType, 
Error :dependent_set_memberEquality_alt, 
productEquality, 
promote_hyp, 
independent_pairFormation, 
Error :isect_memberEquality_alt, 
voidElimination, 
natural_numberEquality, 
independent_functionElimination, 
dependent_functionElimination, 
equalitySymmetry, 
Error :equalityIsType1, 
equalityTransitivity, 
imageElimination, 
imageMemberEquality, 
baseClosed, 
applyLambdaEquality
Latex:
\mforall{}[A:Type].  \mforall{}[R:A  {}\mrightarrow{}  A  {}\mrightarrow{}  \mBbbP{}].    (Sym(A;x,y.R  x  y)  {}\mRightarrow{}  Sym(A;x,y.x  TC(R)  y))
Date html generated:
2019_06_20-PM-02_01_25
Last ObjectModification:
2018_10_07-AM-00_13_27
Theory : relations2
Home
Index