The interesting thing about definitions is that they define boundaries - limits to the subject conceptDef:
1 inability to think - running forward too much, not listening to your environment. being deaf & blind. Going through the motions.
To be able to define a boundary requires a very broad and true awareness of reality. I do not know any area/topic in which my awareness is that broad or true.
So I work at relating to aspects of reality and see where they lead
For example, observing a human, I might look to identify the source/intent of mental inflows, and look at the ability of the brain to reflect those inputs accurately in the current timepath, and the ability of the human to make useful deductions and valid decisions despite existing personality trauma and stresses