The obvious opposing view to what you've just expressed would be that you are your body, and that what you just described as your true self is merely one part of you introspecting about another part of you.
And of course, as far as I'm aware science can say nothing convincing about all of this at present so it's purely an exercise in philosophy and logic.
Not really, I am a non-dualist actually but introducing non-duality in the current context would be a way too off-topic and unnecessary. I prefer not to go into the spiritual stuff beyond what can be easily experienced by everyone unless asked by a person specifically interested in this kind of information.
> it's purely an exercise in philosophy and logic
It's not. It's of little use as long as it is. One has to experience that. That's why I've mentioned the rubber hand illusion. Imagine your hands have been covered from you since you very birth and you have been believing the rubber hands are your real hands for your whole life, then the cover is removed and you experience your actual hands for the first time - it feels like this (approximately). This is how I've got into Buddhism - all the major religions tell you unverifiable things and demand you to believe and here the whole clue is a thing we can experience directly. I've used a quote from the Babylon-5 show because it's a lot about this and you suddenly find yourself understanding the Vorlons' "Who are you?" and "We are all Kosh" after you experience that.
I also suspect this kind of realization may happen to render people nearly-immune to addictions, I would even do some sort of clinical testing if only I had enough money (by the way, some time ago we have already seen news about mindful people being scientifically proven feeling less pain here on HN).
> It's of little use as long as it is.
I didn't mean to imply uselessness; my previous comment was worded poorly. Aside from the spiritual aspects, logic and philosophy alone often manage to achieve (or form the basis of) incredibly useful things.
> the whole clue is a thing we can experience directly
The trouble I have with this is that trying to differentiate between "true self is separate from body" and "body is all there is" based on an experience seems to beg the question. If the former is true, then the experience is what it seems. But if the latter is true, then the experience itself is yet another bodily event - one that results in you (the body in this case) coming away with a false understanding.
A parallel might be someone who feels quite certain about a fact (ie experiences a sense of knowledge), but that "knowledge" later turns out to be false. In light of this, how can we use a direct experience to differentiate the above?
Of course this line of reasoning can be (repeatedly) applied to anything, so at some point I suppose we just have to accept that there are enough separate lines of evidence and that something is presumably true. But I don't think a single direct experience which itself involves the system in question (ie the body) is enough.
As an aside, my rambling on about unknowable-ness isn't intended as an attack against your interpretation of things but rather just general pondering of the (current?) limits of human knowledge and experience.
It seems that I will have to introduce the actual Buddhist (Nyingma/Bön Dzogchen) non-duality interpretation of this in a more or less simplified way to make it (including the "We are all Kosh" part) more clear but be warned, it may sound a way too bizarre. I don't insist it's true and my initial intention was to leave it for the people interested in going this way to discover on themselves as it makes little if any sense before the experience. Ready? The "true self" you can directly perceive this way is just one for every sentient being (my true self = your true self, "by reference" not just "by value", it's the same object, not just same class) and it is kind of the absolute, the only thing that actually exists, everything else (including our feelings and beliefs (our ego), bodies, cars, events and everything) is an emanation of it, like a wave on the surface of a lake. The idea of everything being just an emanation of yourself seems less weird or even rationally obvious if you apply this to "everything in your dreams" but the real life is considered to be a phenomenon of little fundamental difference from a dream. I am not a real guru and may probably explain the things wrong so whoever interested should better watch a lecture of the actual Buddhist (Bön) teacher[1] (it's rather fun, easy to listen and made as free of any religious mumbo-jumbo as possible, the chant in the beginning is very short but the guided meditation that follows the introductory speech is important).
Obviously, the interpretation of a skeptic materialist capable to experience this "true self" and observe their ego is going to be it hardly has anything to do with any kind of absolute and probably is not a real object (needless to say shared between everybody) but just a sort of feeling produced by our bodies.
I believe neither of these interpretations can be rationally proven correct or wrong (it's a transcendental matter) but regardless to which one do you stick to it seems fairly easy to recognize that your feelings, your beliefs, your addictions, your DNA and dopamine receptors are you in the same degree as your left hand thumb is.
Keeping consciously aware of this as constantly as possible may gift a person with an amazing level of emotional balance and having the direct experience of "the true self" can strengthen it to an incredible level (and as a bonus probably let you actually feel less pain when it hurts physically[2]). Deep recognition of the Buddhist interpretation ("rigpa") also gives an awesome sense of union with everybody and everything, blissful presence in every single moment and sets your free of sorrow and worrying.
As for me it took me about 30 years of wondering before I've suddenly found it (by stumbling upon this fairly fun Buddhist monk lecture[1] while being extremely depressed and afraid and searching through YouTube looking for some psychological technique to relieve that). Whatever what I've found is from the philosophic or spiritual point of view, from the pragmatic point of view it seems an extremely powerful key to emotional well-being.
AFAIK there is a fair amount of scientific research effort taking place around mindfulness and other Buddhist stuff, perhaps sooner or later this is going to draw some scientific attention too. By the way, it seems at least some scientifically-minded people happen to come to similar ideas occasionally, e.g. I've recently stumbled upon similar concepts in a book by Itzhak Bentov and was delighted by his scientific manner of exploration of the question of "life, universe, and everything".
That's our bodies, not us. "Every time I find interesting (and fighting)" that people believe they are nothing but a collection of cells, chemicals and feelings. Most people (outside the audience of the HN perhaps) don't even recognize that the feelings are actually the chemicals and have little to do even with the objective reality, needless to say with their true self. Believing you are your body is almost the same as believing that you are your car or your GitHub account. That's not we, that's our bodies, our "cars" with baggage (memories etc) in them, in our true self "we are all Kosh" © Overwhelming majority of people just live in permanent "rubber hand illusion". Getting rid of the illusion and recalling who you actually are is, however, easy as 1-2-3: 1. get cousciously aware of your emotions and thoughts, distance from them and obseve them 2. turn your inner gaze from them to the direction of where do you feel you observe them from 3. recognize that what you see there (it looks like just nothing, just conscious "empty space") is the actual you and you will never be able to "unsee' that. One doesn't need any kind of religion or spirituality to realize this (although it actually is taught in the Tibetan religious tradition of Dzogchen), it is as simple as realizing the rubber hand is not a part of your body.