I'm going to cancel plans with my friends after they invited someone I disagree with
What do you two disagree on?
I find his political views very wrong.
I know sometimes it can be annoying to be around him, however you already made the plans. You should not cancel them just because one person.
It's fine since my other friends don't mind me.
Didn't you want to have fun with all of them? I believe sometimes it's best to cast aside politics and have fun. You never know if that person is a great guy despite his conflicting views!