Nuprl Lemma : strong-subtype-eq1
0,22
postcript
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A
,
B
:Type,
b
:
B
,
a
:
A
. strong-subtype(
A
;
B
)
b
=
a
B
b
A
&
b
=
a
A
latex
Definitions
x
:
A
.
B
(
x
)
,
P
Q
,
Prop
,
x
:
A
.
B
(
x
)
,
strong-subtype(
A
;
B
)
,
A
&
B
,
t
T
Lemmas
strong-subtype
wf
origin
A, B:Type, b:B, a:A. strong-subtype(A;B) 
b = a 
B b A & b = a A A, B:Type, b:B, a:A. strong-subtype(A;B) b = a B b A & b = a A 
x:A. B(x) Qx:A. B(x) T