I had always thought that a thought was who we are at our deepest levĺel but there are some practices that say that thoughts just come and go and not to pay attention to them (I am thinking of meditative techniques which are clearly not scientific)
That seems to be a huge difference in appreciation of a phenomenon that is s constant "companion" (or "expression"?) throughout our days.
Is one right and the other wrong or are both correct and both incorrect if taken too far?
I still think that the thought represents who we are but maybe the fleeting thought does not and it us the aggregate of thoughts over time (and the context no doubt) that is more descriptive of who we are.
i have spent a long time deliberating the same thing - but this does not make me anything like an expert so take what i say as an opinion and not as anything i would argue vehemently....
I spent the longest time never noticing my thoughts, my theory is that everyone exists like this at some point, and some do for their entire lives. that is not to say that i never had thoughts, i, and everyone else, clearly do - how clear and "loud" they are during this period remains to be seen, and may be an unanswerable question - how do you quantify something that by the definition of the premise, hasn't been recognised.
At some point, well into my 20s i reckon, i did start to recognise my own thoughts and the different types of them, in the couple of decades since then i have been dipping in and out of just how deeply i have assessed them. It can be deeply therapeutic and hella traumatising and scary getting into the weeds of your own existence..... i did a lot of meditation, and i think you might have that premise slightly wrong (or i do, both possible), i don't think you are supposed to not pay attention to your thoughts in their entirety, i think you are supposed to pay attention in a detached way, as an observer, curious as to what they are, where they come from and what they mean - but, somehow, don't form new thoughts on these thoughts themselves, as this breaks the spell.
when doing this, its frankly a bit crazy at times, i can see how people can be driven crazy because your thoughts can become "voices" and i could see how people could think that they were coming from someone other than themselves. I never worried that these thoughts were in fact "voices" from another source however, the realisation that all these "voices" were aspects of myself was a revelation and i started, and still do, try to analyse what they mean and represent, but i have split them into two camps - which again is likely incomplete and definitely needs further lower level separations, and these two camps i have labelled "conscious" which is me, my internal narration, the thoughts i actively control (what this "I" is that does the controlling I'm still trying to figure out) - i am doing it right now, i chose to imagine a red ball and there it is, although in this particular instance its more nuanced because I'm not just thinking about the red ball, I'm dictating the typing of it in this reply (this is actually a new revelation for me - ill need to take some notes) - the point being, these thoughts are who i want to be, i want to think good thoughts, i want these good thoughts to translate to good actions. however, i am only sometimes the person these active thoughts want me to be...
the second camp of thoughts, which i have termed biological thoughts, are still me - there are no voices in my head that are NOT me thankfully, but i am not in control of these thoughts to anywhere near the same degree. i am unclear as to how long a biological thought can proceed before i notice it, but as i think everything before my 20 was biological, theoretically its indefinite if you don't notice them. The act of noticing them, i think is the meditation practice. the conscious thoughts i think are turned off often, and i think often automatically although it can be done with ever reducing effort through practice, -biological thoughts i think are much harder to control, and conversely, run automatically until they are noticed - when noticed the CAN but don't always become conscious - which is what i kinda still struggle with to this day.
The reason i call them biological is because since noticing them i have noticed they tend to be more of a nature simpler than my conscious thought, in general but not all the time..... they are fear, anger and paranoia, they seem more ingrained in me and illicit an emotional response far easier than my conscious thoughts. there are also positive thoughts, love i think is far more in the biological camp than conscious, so is amusement and contentment but another reason for the biological term is that we are hard wired to notice dangers rather than positives in our environment - if the temperature is perfect you don't notice, but if its freezing you do - i feel the same applies to these kind of thoughts - once you start to notice biological thoughts you are wired more to noticed negatives - but i am better at noticing positives than i used to be.
One thing i struggle with, and i suspect i am not alone, is not letting these biological thoughts influence or directly affect my actions, again i am better than i used to be, but still lots of room for improvement...... i am a funny, happy and humorous person, but these background biological thoughts can and do take the forefront and anyone who knows me well would have no issue if i added "occasional grumpy bastard" to that wee limited list of personality traits...... i don't have anything like an infallible ability in stopping negative biological thoughts becoming negative conscious thoughts, i doubt i ever will - but i am absolutely improving i believe (wife might disagree

) and i think, in fact i actively believe this analysis and improvement is my reason for being - but now I'm getting too deep.... ill keep trying and seeing what else i come up with.
So, conclusion, i think we have layers of thoughts that are both noticed and not and that status is itself interchangeable, i believe the act of trying to absorb these facts and reality into your own version of existence is paramount, even if it can never be completed in this life. conversely, i do toy with the idea that doing so might be dangerous - i was certainly less crabbit in my early 20s when still entirely biologically driven, but this side of things is only something i toy with as a devils advocate to myself.....cos I'm awkward.
Apologies for the lengthy response, i joined this forum to discuss my views on exactly this stuff and your post was the first i have read the really let me let loose with the conscious thoughts of it all.
as said at the start though, i am making all this up in my own head from what i know, one thing i am fairly confident in is that i am very fallible and all this might be utter rubbish, but for now, its where i am at.....feel free to rip to shreds.....