Thinking is taking what is real and replacing it with a token.
This token may be manipulated in any way at all.
It is, in fact, a simulation of reality.
This serves to project what might happen, if...
A useful tool, then, to gaze a short time into the future, to see what is likely to occur.
Or a short time into the past, to determine what went wrong.
It is far more practical, often, to design a house on paper, before physically building it with no idea of what the result will be. Unless, of course, you are so certain of your ability to improvise and problem-solve, that plans become wasteful of time.
The big trick to thinking, and the thing that has been almost universally forgotten, is to reconvert the tokens that comprise thinking, back into reality, after the thinking has taken place.
Remember: thinking is the conversion of reality into easily-manipulated tokens of reality.
To complete the process, it is necessary to re-convert those tokens back into reality.
Or you end up existing in a hypothetical world of tokens which have completely replaced reality.