I have a friend who struggles socially, he is both a highly skeptical person and intelligent (IQ133) and that is what I like about him.
but It really pisses me off when we socialise with other people and he becomes arrogant, not so much Lording over people but continually challenging them until he brings them down mentally.

Its making it difficult for us to expand our shared social group.
What advice could I give such a person to reduce the arrogance ?