I am an INTJ or "Rational Mastermind," "Scientist," whatever but basically that's me.
Here are a few good links about this personality:
http://www.mypersonality.info/personality-types/intj/
http://www.personalityzone.com/view/temperament/mastermind.html
http://en.wikipedia.org/wiki/INTJ#See_also
http://en.wikipedia.org/wiki/Mastermind_%28Role_Variant%29
http://fuzzy.snakeden.org/intj/ (I really like this one especially rule 5)
http://www.keirsey.com/handler.aspx?s=keirsey&f=fourtemps&tab=5&c=mastermind
For those of you who want to get to know yours go take these tests:
http://www.keirsey.com/aboutkts2.aspx
http://www.mypersonality.info/
Dealing with INTJs
1. Be willing to back up your statements with facts - or at least some pretty sound reasoning.
2. Don't expect them to respect you or your viewpoints just because you say so. INTJ respect must be earned.
3. Be willing to concede when you are wrong. The average INTJ respects the truth over being "right". Withdraw your erroneous comment and admit your mistake and they will see you as a very reasonable person. Stick to erroneous comments and they will think you are an irrational idiot and treat everything you say as being questionable.
4. Try not to be repetitive. It annoys them.
5. Do not feed them a line of bull.
6. Expect debate. INTJs like to tear ideas apart and prove their worthiness. They will even argue a point they don't actually support for the sake of argument.
7. Do not mistake the strength of your conviction with the strength of your argument. INTJs do not need to believe in a position to argue it or argue it well. Therefore, it will take more than fervor to sway them.
8. Do not be surprised at sarcasm.
9. Remember that INTJs believe in workable solutions. They are extremely open-minded to possibilities, but they will quickly discard any idea that is unfeasible. INTJ open-mindedness means that they are willing to have a go at an idea by trying to pull it apart. This horrifies people who expect oohs and ahhs and reverence. The ultimate INTJ insult to an idea is to ignore it, because that means it's not even interesting enough to deconstruct.
This also means that they will not just accept any viewpoint that is presented to them. The bottom line is "Does it work?" - end discussion.
10. Do not expect INTJs to actually care about how you view them. They already know that they are arrogant bastards with a morbid sense of humor. Telling them the obvious accomplishes nothing.
