Both INFPs and INTPs kind of suck at providing evidence for their beliefs. It's basically "this is true because I said it's true. It makes sense and if you can't see it you're blind." ENFPs and ENTPs don't seem quite as bad, I think because of higher level Je. INTPs in particular will always try and "reason" with you why you must be wrong. They use "logic" to get themselves out of anything. INFPs do the same thing with personal matters.
Basically, you all suck because you aren't TJs.