I'm usually extremely pensive. I brood plenty. Even if I wash the dishes, vacuum, eat, play an instrument or a videogame it usually goes on in the background, as if muscle memory just took over specifically to allow me to continue brooding, not seldom about things as morbid as the true sadness behind child obesity, still there existing physical torture on this earth, contemplating the reasons a person I knew might have had to commit suicide, methods of capital punishment and the like.
Of course, thoughts are rarely linear. There's always tangents, explanations, complementary ideas, analogies and examples which fortify the making of a pattern.
I find myself not being very saddened at all by such things, but I do often feel it "helps me grow wiser". It probably doesn't, but after one of these sulking sessions, which usually last the whole day when they do happen, I feel grave, serious, mature. But not sad.
Most of the time I am fiery and passionate about the ways in which I try to better explain my conclusions and ideas and very very bored when "forced to look" at "the real world". The fact that turning outward tires and bores me out so much makes me feel very slightly angry: not at myself, but at others for disliking theory and the deduction-induction cycle and forcing their real-world-contemplating will upon me.
I am often tired mentally, as I sleep around thirty hours a week when not on vacations.
I feel rather sad at the absurdity of life and the need of pleasure (yet rarely do I feel sad because of other things).
I occasionally feel disgust at someone when they attempt to formulate logically coherent statements "backed by the facts" but are stubborn to modify their logic, their premises, their point of view or any combination of the above when outright (often by logic) proven wrong.
For example, an acquaintance at school was discussing with me the book Beyond Good and Evil. He asked me what words I would use to substitute "good" and "evil" to eliminate them -- use some more meaningful words instead. I replied that good is that which increases power, influence and control, and vicecersa. He went on to say, "To me, something is good if it meets your expectations, even if you didn't expect it".
I explained that it is impossible, by definition, to expect something to not meet your expectations for that very something. He got what I was saying, but tried to refute me with poor, poor circular logic and then tried to change the subject. I felt a little disgusted.
Most of all, I usually feel both alone and lonely (and I quite enjoy it) except when speaking to a particular INTJ friend.