Thoughts, in and of themselves, constantly question, respond, elaborate, and scrutinize. As they yield to their own limitations, they remain unchanged. Your mind, flawed and unquiet, is not distinct from these musings. That which is not contemplated, remains unknown. Attention is the key to understanding
The question is how to find out... as a start, notice, that as opposed to thinking, which travels as time, attention is always now, never as time
First, I don't know.
I can guess, imagine, think...
That 'I don't know' is the fact, to which "I" attend (or not)
Let the question (that you asked) hover in you. Look at it. At what it does to you. All this is attention.
Is "I" ever attend?