With permanence postscript.
In Buddhism, the term anattā (Pali: अनत्ता) or anātman (Sanskrit: अनात्मन्) refers to the doctrine of "non-self" – that no unchanging, permanent self or essence can be found in any phenomenon.[note 1] While often interpreted as a doctrine denying the existence of a self, anatman is more accurately described as a strategy to attain non-attachment by recognizing everything as impermanent, while staying silent on the ultimate existence of an unchanging essence.
The issue is Siddhartha wrote in Sanskrit, and I'm reading in English. I don't exactly trust La Wik to understand nuances.
However, at least regarding Western interpretations of anatta, it's suicide for the squeamish. Too much of a pussy to drag a knife down your arm? That's cool: meditate on destroying your ego until you don't have a soul anymore and become a zombie. That's dumb, let's fix it.
1: no fixed essence.
Impermanence is very real (although it’s a blessing, not a curse). We have a nature, as do all other entities and events. Everything has a list of properties which describe it; the least-redundant form of such a list is its essence. E.g. maybe a rock is a collection of misaligned silica crystals, and likewise we can describe what silica is. However, it changes constantly. You can’t step into the same river twice, as they say – you can’t even be the same person who stepped in the river the first time, never mind the river itself.
More, I prefer to describe everything as an event. Stable "objects" are merely events that tend to cause themselves to re-occur. They are events that re-create themselves, which re-creation re-creates itself again. A door right now causes a door to be in the doorway in the next second, which causes a door to be there in the third second, and so on. By contrast a fire doesn't cause the same fire to re-appear.
Yet more: to write out the full list of an event's properties (even if you have the immortal capacity to not die before you finish) means writing out the list of properties of the entire universe. There are no hard boundaries; all is one (although the Dao looks like two everywhere). To fully describe an event means describing the things it is currently interacting with, which means describing what they, in turn, are interacting with, and then you end up having to describe literally everything, the alpha and the omega. Luckily full understanding is not necessary to get on with it; a distinctly impoverished list of properties can get you like 99% of the way there.
2: physics, as an objective, external world, is somewhat illusionary.
It is in fact not external – treating it as external is something like a shorthand or a compression. It’s close enough that it works, but if you truly want to understand, you have to realize the physical world you see is, to summarize for brevity, just you, but again. It’s me over here, and it’s me over there too.
What we perceive as the "external" world are in fact our internal noumena which we don't have willful control over. The blue cube "out there" is in fact your thought/perception of a blue cube, and thoughts are inside. What makes the thought fixed is that it's [our] thought instead of purely [your] thought; you can't change my mind, just as I can't change yours, so if we both have a thing in mind at the same time, neither of us can change it. The "external" world isn't outside, it's merely shared.
Note that this is more or less my repair of Descartes' proof of God. Minds actually can't share; that's the nature of subjectivity. Unless, that is, they are in fact both part of a greater mind. An overmind, if you will, which is imagining two minds that perceive themselves as separate. Also, imagining a world so vividly and consistently that we can't tell the difference between that consistency and lawful physics.
3: even Easterners say they have no "real" ego any more than, say, Lara Croft has a "real" ego. I would say Lara Croft really does exist, rather than that I don’t exist, except that Lara Croft is distinctly less complicated than I am.
Lara suffers* a lot more from impermanence. I can’t
be switched off at the push of a button, and if I am switched off, I
can’t be easily switched back on either. My complexity comes with
inertia, you might say. As a result, stuff done to me (or by me) is much
more lasting than stuff done to Croft. This, however, is a difference
of degree, not a difference in kind.
*the joke is impermanence is not suffering
Likewise, it's not that dreams aren't "real" exactly. Rather, dreams have bonus impermanence. The long term is truncated, 0) making the short term much more valuable by comparison and 1) meaning the total value of events in a dream much, much lower. We don't much care what happens in dreams because, ultimately, much less happens in dreams. It's not actually 0 events, though.
This is important, because sometimes physical-world events are also highly impermanent, and yet it's easy to treat them as "real" even though they have consequences exactly of the same magnitude as actions in a dream.
The issue is Siddhartha wrote in Sanskrit, and I'm reading in English. Maybe this is exactly what Gautama-sensei meant by anatta. Or maybe he would virulently disagree. Maybe I even missed the point. Hard to tell. It's easy to imagine he would know more about it than I do.
P.S. Mistakes cut off future possibility of virtue. If permanence were real, mistakes would accumulate until they choked out all existence. Impermanence forgives all your mistakes, sooner or later. The price of this forgiveness is having to re-up your good decisions periodically.
Try to remember that if it feels bad to re-up a particular good decision, you need to start doing accounting. Most likely the event's impermanence is too high and it's not worth doing. The problem isn't impermanence, the problem is you want unprofitable things to be profitable, and Gnon says, "No."
P.P.S. Sadly the modern world is highly anti-intellectual, so it's unlikely I will ever meet someone a) willing to explain on Siddhartha's behalf & b) not too couch potato to grasp the intended idea. Gotta do your reps unless you want to give me carte blanche to walk all over you, scholastically speaking.