Metamath Proof Explorer


Theorem ssbri

Description: Inference from a subclass relationship of binary relations. (Contributed by NM, 28-Mar-2007) (Revised by Mario Carneiro, 8-Feb-2015)

Ref Expression
Hypothesis ssbri.1 𝐴𝐵
Assertion ssbri ( 𝐶 𝐴 𝐷𝐶 𝐵 𝐷 )

Proof

Step Hyp Ref Expression
1 ssbri.1 𝐴𝐵
2 ssbr ( 𝐴𝐵 → ( 𝐶 𝐴 𝐷𝐶 𝐵 𝐷 ) )
3 1 2 ax-mp ( 𝐶 𝐴 𝐷𝐶 𝐵 𝐷 )