Hi viv;..I disagree with your conclusion re that my explanation is a metaphor for thinking.
The first definition of the word spirit according to my dictionary is ; spirit noun, force giving life to a body.
That force to my understanding as a noun is basically the air we breath(mostly oxygen) that force can be calm or violent ie we still have to breathe even in a very forceful hurricane.
Force in terms of physics is seen as an influence which can produce a change or reaction to a physical system.
Our bodies are physical systems, therefore the spirit is the force which gives rise to our bodies functions which in turn causes the influence on our brains (thinking processes ) which in turn controls our actions therefore making us the people we are.
Spirit in human terms is imo not a metaphor for thinking, but rather the air we breath.
Further dictionery definitions ŕe ghosts supernatural etc believed by many , Is to me delusional hogwash.
Best wishes