He seems pretty INTJ to me, with the caveat that the change he wants to see in the world is based on something that looks a lot like Ti. This sort of illustrates my difficulties with the distinction between Ti and Te, as plenty of people are both motivated by the intrinsic and extrinsic value of knowledge and understanding.
The reasoning for INFJ seems legit, but Te seems present, and I can't imagine him having a feeling function above his monstrous T. He is IMO one of the most logically consistent public figures going round, and there's little evidence of him valuing emotions above rationale in any way.
When he does these talks, it's almost as if he's bored. He's already figured out all his positions, he's thought about it more. He knows there's very little chance of either person changing the other's mind, and seems like he's only there to get his message out to viewers.
Edit:
@CC
He does do a good job of that, and it's to his credit, but I don't see his relatability as comparable to his precision. He's just as scathing as Dawkins or Hitchens, but tempered by the need for composure. He's a professional Devil's advocate and his interactions seem merely instrumental to the goal of spreading his views (or debunking the views of others).