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Metamath Proof Explorer

Theorem relrpss

Description: The proper subset relation is a relation. (Contributed by Stefan O'Rear, 2-Nov-2014)

Ref Expression
Assertion relrpss Rel [⊊]

Proof

Step Hyp Ref Expression
1 df-rpss ⊢ [⊊] = { ⟨ 𝑥 , 𝑦 ⟩ ∣ 𝑥 ⊊ 𝑦 }
2 1 relopabiv ⊢ Rel [⊊]