Why do you think he is INTP? He seems to have a lot of immature, self-absorbed tertiary Fi, which is what makes him funny and gives him this childlike quality under his robotic, cool exterior. Him having a good memory has absolutely nothing to do with Si, and I've known at least one INTJ tell me that they pride themselves on their consistency.
I'm also not sure why an INTJ would be sneakier than an INTP. To me that is the worst argument in [MENTION=13260]Rasofy[/MENTION]'s analysis. Even Keirsey never said this.
Also TiNi would be ISTP, or NiTi would be INFJ, and he has terrible Fe. Like him saying his new computer has Windows 7 instead of Windows Vista, making his new computer more user friendly, and he doesn't like that.
And he doesn't even know what a friend with benefits is, and he says "I sense that's inauthentic and I have no idea why"...which seems more like tertiary or inferior Fi.
His face also lacks expression most of the time, except for when he purses his lips, and in one episode he says "Oh Mario [from the video game] if only I could control everyone the way I control you!" Why would an INTP say that? Their Fe is inferior. That smacks of Je.
I don't disagree that he is INTJ-like, and what you said about TiNi would generally be true - I'd be typing Sheldon as an INTJ (or even ISTP) except he really doesn't seem to exhibit any of the paradigm-shifting that is the hallmark of Ni. His past achievements and history ring more NTJ than NTP, but those are both external indicators and are not a concrete basis for making cognitive type calls.
The thing about INTPs is they might be Ps, but they are still Judging dominant and as such they can be
very controlling. They decide with Ti-Ne that things ideally
ought to be a certain way, and that is
the way they want them to be, and no other way makes as much sense, so it really must be that way. My INTP dad used to reorganize
my car for me because he felt like things should be in certain places and I was not putting them there (and he genuinely felt that life would be better for me if I used the system that to him seemed so clearly right). It's different from Ni-Te because Ti-Ne is more interested in finding the one theoretical logical ideal out of all solutions and adhering to that, regardless of difficulty of implementation, while Ni-Te will be more open to finding an expedient, effective solution, and will change its ideal if the ideal is not externally effective. I see more of the former in Sheldon - nitpicky nitpicky nitpicky.
I also think it's pretty clear that Sheldon has at least some obsessive compulsive traits (if not full OCPD), which make him more J-like. He's pretty narcissistic as well, which makes him seem more confident and J-like than your average INTP, and may well have spurred him to be more productive and goal-oriented than your average P. All IxTxs seem to have that sweet hidden childish quality too - I think it's more about low-level F than about Fi in particular. I do think he has good Si, though - and he does have a photographic memory to boot. I've heard good arguments for him being ISTJ, including his taking comfort in regularity and order, his distaste for chaos, and his harping on "experimentation and observation" as a scientist (which also suggests Ne over Ni), except I cannot for the life of me see an ISTJ devoting his career to string theory, which may or may not be true and/or useful and is more than probably wrong at least in part.
I guess what I'm saying is if we're just using pure MBTI 4-letter dichotomy, he's totally INTJ. But if we're going by functions... eh. I think it kind of fails for Sheldon's character. I just don't see much Ni in him. His N seems more Ne - not twisting the box in a multitude of ways, but just dismissing the box. I would type him Ti-Te-Ne-Si-Ni-Fe-Fi-Se.
Rasofy said this a while ago, and I agree:
Rasofy said:
Letter by letter, INTJ is a good guess, but judging by his speaking patterns, I think he is a sort of ''J INTP''. If that makes sense. He is in a class of his own, really. We don't see many Sheldons around. But i think the closest to a Sheldon Cooper is someone that's in a TiSi loop. We can see good examples around.