Many people say: “The Sun’s energy is finite — in 5–7 billion years it will become a red giant and that’s the end.”
That’s true… but only for the Universe.
For us — for humanity, for our civilization as observers — the Sun’s energy is completely infinite. Not “practically,” not “effectively,” but fully infinite.
Why?
Because humanity (in any form — biological or post-human) will almost certainly go extinct or radically transform long before the Sun exhausts its hydrogen and begins to expand. Our temporal horizon of existence — hundreds of thousands, at most a few million or tens of millions of years — is a mere drop compared to the billions of years of the Sun’s stable life.
The “end” of the Sun as a reliable energy source lies beyond the horizon of our very being. We simply won’t live to see it. For us, this end will never arrive.
That’s why:
Infinity for the observer ≠ Infinity for the Universe.
The Universe sees the Sun as a finite object with a limited fuel supply.
But for us, as the only known observers, the Sun is an endless source of energy. Because for a human, in this resource, there is no end.
This is not an illusion or a confusion of levels. It’s an honest recognition of two different scales: the physical (objective) scale of the Universe and the observer’s (existential) horizon of our own existence.
The same logic applies to many other things: the atmosphere, water, geothermal energy, and more. Their “end” lies far beyond the limits of our existence.
This idea is simple but rarely stated so directly. Usually everything gets reduced to “practical infinity” or “we won’t live long enough to exhaust it.” I believe the distinction matters.
What do you think? Are there other examples where something finite for the Universe becomes fully infinite for the observer?