But it is possible to let both go - esp. the cynicism. The humor is always bubbling around in the background ready to come out because, for all of our seriousness, INTPs very often value and enjoy humor. However, the type of humor can change - less biting, more playful. However, for that to happen I'd hazard a guess the average INTP has to feel he/she is in a very safe place with someone - both emotionally as well as physically too I think: you want to see an INTP at their very warmest get them in a private setting - from what I can tell most of them are not as open to displaying emotion in a public or semi-public setting.