Self-Absorption can be found everywhere from the least functional homeless person to the highest functioning scientists, statesmen, intellectuals and psychologists. It isn’t a function of a thought disorder overall.
It is, however, related to some very definite, and with practice, obvious, kinds of thinking.
First of all, Self-Absorbed People tend to not think morally. Even if they could teach college level classes on morality, they don’t think that way in their own lives. I find it useful to think in terms of Kohlberg’s Moral Development Scale, which, although it is old and has been updated over the years, is the most useful way to conceptualize moral thinking. The issue here is not what you decide is the right thing to do morally, but the way you reach that conclusion.
Although this is an oversimplification, there are three steps in moral development.
The “What’s in it for me?” or Pre-Conventional Stage, in which the individual only seeks to avoid punishment and get whatever they can.
The “Good citizen/bad citizen” or Conventional stage in which the individual follows the rules in the best interests of family, social group or country.
The Post-Conventional Stage, in which the individual makes their moral decisions based on higher principles or causes.
It is almost universally observed that Self-Absorbed People do not think any higher than the lowest moral stage. The only morality that they practice is “What’s in it for me.” The closest they can come to describing their morality are really just excuses or rationalizations. Seldom more than “I‘ve got mine, you get yours.” Even when they might appear to be struggling with a moral issue they are really just looking for ways to rationalize doing whatever they want.
Secondly, even though they don’t hold themselves to any kind of moral standard, they use morality and moral issues against other people. Judging them, chastising them, or controlling them.
Third, their moral thinking is concrete and superficial. There is, emotionally speaking, no meat on the bone. They think that if something can be rationalized that makes it rational, if they can justify it that means it’s justified.