Are you sure that in general INTPs don't need praise? I think that is more a Neuroticism/Emotional Stability thing (a factor left off of MBTI). Neurotics are more needy (which, I am beginning to believe, for INTPs, is a good thing).
sure intps need some form of praise just like everyone else but when it's "fished for" it feels like it just doesn't count... like this thread.
kinda like, to use a very stereotypical example, when a woman asks "do i look fat in this dress?" how about you look in a mirror and see for yourself. 9 times out of 10 people will just humor you and it won't be genuine.
if you want to really praise an intp, they'd have to have done something theyre proud of first of all. second, someone who is knowledgable in his/her area of expertise would have to view and critique the work in question and give all sorts of technical feedback. third, it can't be a type of "i like him so i'll give him a compliment" sort of appraisal but more of a "he knows what he's doing and does it well" sort of thing.
to be clear, sure i understand other people's need to have all sorts of gushy emotional praise and from time to time i indulge them but it's never automatic and i rarely mean it, it's just what's expected from the role i'm playing be it friend or relative. i should note as well, half of it is i don't want to spend the time of giving my honest view then trying to explain why i didn't think their shit smelled like roses.
notes: sorry for the multiple posts, i've spent time thinking about this subject in the past so my thoughts are already gathered. as well some of this may be just specific to me, ymmv.