Thinking begins with doubt. It involves a search directed at removing
the doubt. Thinking is, in a way, like exploration.

We search for three kinds of objects:

possibilities, evidence, and goals.

1- Possibilities are possible answers to the original question, possible resolutions of
the original doubt.

2- Goals are the criteria by which you evaluate the possibilities.

3- Evidence consists of any belief or potential belief that helps you determine the
extent to which a possibility achieves some goal. Asearch for evidence might initiate a whole other episode of thinking, the goal of
which would be to determine where that evidence can be found.  (p. 7,8)