Could it have something to do with language?
“Don’t think of a sailboat.”
Comprehending the above sentence seems to require that I translate the word “sailboat” into a concept that brings with it images, etc. So, maybe it’s that simply comprehending the request, “Don’t think of a sailboat,” requires the brain to think of a sailboat.
But it does seem to be more than that. Because a coworker just made a statement about coffee. I have not – to my knowledge – been thinking about coffee. But if I was told that I shouldn’t think of coffee at all today, I’d likely be thinking about coffee. I noticed this when I first started meditating. I would attempt to focus on the breath. And when a thought would arise, I would immediately try to squash it (“Don’t think of the work demo I have to do tomorrow.”) and come back to the breath. But I quickly learned that the buried thought would rush back and be even stronger. The level of rumination increased with my attempts to just “not think of” the thought. What I found to be a useful approach was to acknowledge the thought, and without judgement observe my mind thinking the thought. It seemed (for me) to take the power away from the thought itself and towards the internal processes and related emotions that supply power to thoughts.
Is there a hypothetical evolutionary reason anyone knows about?