Which explanation do you like the most?
- Thinking is the act of analyzing a particular thing in the mind using the rational concept correspondence to thing that either exists or not.
Thinking is nothing but the sensory systems forming quantum particle dioramas in the brain, The evidence of that is the same part of the brain is stimulated when something is sensed, and when that same thing is remembered.
The ability to discriminate irrelevant features of an object -call it an animal, person, thing, situation, you fill the blank...- to focus on one particular feature of the object of study to define it, and assimilate it as a information to be utilized down the road. In short, the act of thinking can be summarized as an abstract analysis of a challenging situation.