It seems to be more than a simple idea, though. I directly experience the self. There is an observer inside the brain "seeing" the thoughts (regardless of whether it is being carried by them or not). No?
That is the handy, useful, intuitive, day to day understanding certainly.
That it is impermanent doesn't mean it doesn't exist, right? Some people say all the atoms of the human body are eventually replaced in some years. That doesn't mean there is no human there, it seems to me. The same may apply to the self.
Again, this is our mundane understanding yes. Entities, not processes. Like nonself, impermanence is a fundamental Buddhist idea. And because of impermanence, all
things (including mental concepts) are empty of inherent, abiding selfhood.
Your atoms comment is key. But the process is not years. The whole universe is contantly changing, "you", "me", the weather, Mount Everest, the Milky Way...It is a matter of perception and time. Why should the rest of the universe consist of constantly changing energy/matter, but not humans? Clearly, we do. This must therefore include such notions we have of "observer", the "mind", the "self" - where do they reside and how can they buck the trend of the total interdependence and change occuring in the rest of the universe? If one accepts that a person ("bounded" by the skin) consists of constantly changing atoms (drinking, eating, digesting, urinating, defaecating, breathing, body repairing, etc etc etc) then no thing or concept (observer, mind etc) can be fixed or separate from the rest of the universe because the "place" these (whatever they may actually consist of) are meant to reside (our body) does not have fixed, independent selfhood. You consist of certain atoms (matter/energy) right now. Where were all those atoms yesterday, last year, when you were born, before you were born, at your death, after your death? (Ignoring notions of a Big Bang etc) they have always existed and always will; it's just that some of them briefly constitute "you." The handy illusion of an abiding self (able to observe thoughts) is hard to lose, given its usefulness and it being seemingly self-evident (haha). Thus we think we have a separate self, separate from the rest of the universe. The claim of Buddhism, of anatta, is that we are not and that in a less relativistic way, we are empty of selfhood. When we watch a film, we
know it is not a real moving image, we know it is a series of quickly presented still images (or has it gone all digital?!) but having this knowledge does not cause the illusion to immediately disappear.
Anyway, that's the claim, right?
That there is no selfhood, yes.
Do you agree with this teaching?
Yes,
I do.
If one does not accept it as being true then one is rejecting Buddhism. It is one of the three essential foundations. (And as I noted, one of the others being impermanence).
Do you know you have no self?
My understanding is that anatta is a more accurate description of a fundamental aspect of all (apparent) things and hence is a vehicle for the practice of living.