Well, it is of course a 'social situation' you know. But of a different kind than your typical conversation in school or university, or parties or what. In my course (it was a sport course in the university, not in a dojo; that is lika a club of Aikido) there were 30 people beginning and after a few sessions there were only aboutten left
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And so the people staying are the ones who are really interested. Aikido is not very solitudal. I mean, most of the things you train you train with partner. Aikido is not like some other martial art, where you can practise katas (moves) all for yourself all day. Aikido is a martial art, where you interact quite much with the attacker. That means the objective is to harmonise_/synchronise with the strength and energy (kinetic energy; i'm not esoteric here
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) of the attacker and barely have to use own strength. You melt with the movement of the attacker and when you are out of the attack way you just guide it in another way and the attacker goes to ground. It really is quite beautiful and interesting to watch and to do. There is much body physics (mechanical physics).
So, in light of the 'INTP-suitability': I think it is suitable. Although it is of course a social situation, and Aikido only works with a partner (note that the 'atacker' normally is called partner
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Aikido really is not something for aggressiveness), if the people are not so nice as to talk with them, you can just focus on your training a be the 'mute' partner. It is in any case better to not talk during training. So if you don't have problems with having physical contact with other people there should be no obstacle.
Ogion
P.S.: Oh and one thing: Aikido is something which really needs a long time to become very good at. If you look videos of Aikidoka on Youtube (and there are some good ones) and would like to do these things yourself be aware that it rather takes you years to accomplish. In the short term Aikido can give you a good amount of body control (and hopefully fun
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)