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Step * of Lemma strong-subtype-void

∀[T:Type]. strong-subtype(Void;T)
BY
{ (Unfold `strong-subtype` 0 THEN Auto THEN (At ⌜Type⌝ (D 0))⋅ THEN Auto) }

1
1. T : Type
2. Void ⊆r T
3. x : {b:T| ∃a:Void. (b = a ∈ T)} @i
⊢ {x ∈ Void}

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Latex:

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Latex:
\mforall{}[T:Type].  strong-subtype(Void;T)


By

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Latex:
(Unfold  `strong-subtype`  0  THEN  Auto  THEN  (At  \mkleeneopen{}Type\mkleeneclose{}  (D  0))\mcdot{}  THEN  Auto)

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