"You cannot look twice at the same river; for fresh waters are ever flowing in."Heraclitus. As such reality is always changing, but always the same, just rearranged.
As for an apple always falling down, if one accepts the idea/fact of electrons, it is theoretically possible, though highly remote, that all the electrons could go in one direction, say up, and thus an apple could fall up, despite gravity.
A truth, by definition, is a truth, either in Turkey or America, otherwise how could it be true. This is not to say that truth cannot change over time, as definitions undergo change, due to more information or perhaps merely more ideological input, this can happen. The succeeding truth will only remain true until another truth can displace it. This is easier on an ideological basis than a mathematical or scientific one.
In the end, like Socrates, everything depends on the definitions of the terms we use. Change the terms and what is true may change, the same goes for mathematical equations.
Reality may be more like life, it exists, or so we tend to believe, but has no set form, or how it may appear to any given person/one.
Was married to a mathematician for some years, it was way beyond me, as to the ability to do it, but could at least follow the reasoning of how it was done and why. Great fun.
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