He is a rationalist (...)

He had rationalised (...)

(...) despite being informed that a previous partner had been infected (...)

So uh, let's run down the checklist...

[ X ] Proclaims rationality and keeps it as part of their identity.
[ X ] Underdog / against-society / revolution mentality.
[ X ] Fails to credit or fairly evaluate accepted wisdom.
[ ] Fails to produce results and is not "successful" in practice.
[ X ] Argues for bottom-lines.
[ X ] Rationalizes past beliefs.
[ X ] Fails to update when run over by a train of overwhelming critical evidence.

Well, at least, there's that, huh? From all evidence, they do seem to at least succeed in making money and stuff. And hold together a relationship somehow. Oh wait, after reading original link, looks like even that might not actually be working!