1. Conflict and contradiction are the deepest truths of reality.People who are familiar with the deep blue portion of the blogosphere can testify to the proliferation of this type of thinking.
2. Reason is subjective and impotent to reach truths about reality
3. Reason's elements - words and concepts - are obstacles that must be un-crusted, subjected to Destruktion, or otherwise unmasked.
4. Logical contradiction is neither a sign of failure nor of anything particularly significant at all.
5. Feelings, especially morbid feelings of anxiety and dread, are a deeper guide than reason.
6. The entire Western tradition of philosophy - whether Platonic, Aristotelian, Lockean, or Cartesian - based as it is on the law of non-contradiction and the subject/object distinction, is the enemy to be overcome.
The result, for those who prescribe to this methodology, is that no matter how much evidence you lay out that things are one way, if they feel that matters are the other way then they refuse to accept the logic. After all, logic and reason have no use in determining reality. In fact, the more one feels correct, the more correct the position. Hence the strong reliance on volume, obnoxiousness, and profanity.
Another result is the vitriolic response to criticism. If views of reality derive from feelings, then criticism can not be anything other than personal. In fact, it can be taken as an attempt to completely negate the validity of the individual. The flip side of the coin is that if a person believes something that one considers wrong, then the person must be either stupid or evil. Yet more reason for obnoxiousness and profanity.
I don't really need to be limiting this discussion to the leftist elements of society. The far right tends to be just as guilty (see: Intelligent design). If anything, the religious right is more in keeping with the philosophical tradition of Kant and Hegel. Those two gentlemen attacked reason with the explicit intent of bolstering religion. Say what you will about ID supporters, they muster on and don't take evidence as an answer.
Edited to replace the numerical list with a more comprehensive list found in the book. I should have highlighted better the first time through.