27 lines
654 B
Text
27 lines
654 B
Text
namespace S1
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axiom I : Type*
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definition F (X : Type*) : Type* := (X → Prop) → Prop
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axiom {u} unfoldd : I.{u} → F I.{u}
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axiom {l} foldd : F I.{l} → I.{l}
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axiom iso1 : ∀x, foldd (unfoldd x) = x
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end S1
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namespace S2
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universe variables u
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axiom I : Type.{u}
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definition F (X : Type*) : Type* := (X → Prop) → Prop
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axiom unfoldd : I → F I
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axiom foldd : F I → I
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axiom iso1 : ∀x, foldd (unfoldd x) = x
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end S2
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namespace S3
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section
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hypothesis I : Type*
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definition F (X : Type*) : Type* := (X → Prop) → Prop
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hypothesis unfoldd : I → F I
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hypothesis foldd : F I → I
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hypothesis iso1 : ∀x, foldd (unfoldd x) = x
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end
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end S3
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