Nuprl Lemma : inject-composes
∀[A,B0,B1,C:Type]. ∀[f:A ⟶ B0]. ∀[g:B1 ⟶ C].
  (Inj(A;C;g o f)) supposing (Inj(B1;C;g) and Inj(A;B0;f) and strong-subtype(B0;B1))
Proof
Definitions occuring in Statement : 
strong-subtype: strong-subtype(A;B), 
inject: Inj(A;B;f), 
compose: f o g, 
uimplies: b supposing a, 
uall: ∀[x:A]. B[x], 
function: x:A ⟶ B[x], 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x], 
member: t ∈ T, 
uimplies: b supposing a, 
inject: Inj(A;B;f), 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
subtype_rel: A ⊆r B, 
so_lambda: λ2x.t[x], 
so_apply: x[s], 
strong-subtype: strong-subtype(A;B), 
cand: A c∧ B, 
prop: ℙ, 
guard: {T}, 
compose: f o g
Latex:
\mforall{}[A,B0,B1,C:Type].  \mforall{}[f:A  {}\mrightarrow{}  B0].  \mforall{}[g:B1  {}\mrightarrow{}  C].
    (Inj(A;C;g  o  f))  supposing  (Inj(B1;C;g)  and  Inj(A;B0;f)  and  strong-subtype(B0;B1))
Date html generated:
2016_05_16-AM-10_21_15
Last ObjectModification:
2015_12_28-PM-09_22_39
Theory : new!event-ordering
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