It's unfortunate that he summed up this realization by saying, "When you realise that the dumbest person in the argument is on your side, that means you’re on the wrong side." It begs the question of how you decide who the dumbest person is, and it seems like it would reinforce whatever a person's current attitudes are, rather than move them to change.
> When you realise that the dumbest person in the argument is on your side, that means you’re on the wrong side
I don't think this is necessarily a good rule of thumb in general. Lots of topics have 3 levels of understanding, where the dumbest level and the smartest level have the same answer but for different reasons, and there is an incorrect middle level that is tempting if you know just enough to be dangerous.
Take flat earth for example. It's not the very dumbest people who think the earth is flat. The dumbest people just repeat what they learnt at school! The dumbest people are not remotely open to adopting new and strange ideas. The people who fall for flat earth are those who are smart enough to entertain an unusual perspective, but not smart enough to refute it.
