No, there are actually a lot of things we can measure and study that are unobservable with our senses
The way we measure things is by making them observable to our senses. I can't see radiation, but I can read a Geiger counter. Radiation is, therefore, capable of being observed.
and a shitload of verifiable ways in which our senses either misinterpret reality or completely fail to perceive it
Again, everyone seems to be reading this as, "Actually, senses are perfect and incapable of being fooled." Which I never said anything remotely similar to. No shit they can be fooled. This has zero relevance to the discussion.
Let me explain this again.
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Stars that leave the observable universe, by definition, cannot be observed. There is no way to verify or falsify any claims that are made about them.
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Physicalism states that matter continues to exist regardless of our ability to make observations about it.
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Therefore, physicalism claims that stars that leave the universe continue to exist, even though there is no way to verify or falsify this claim.
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Therefore, either physicalism is wrong, or verificationism, the idea that our claims need to be supported by evidence and be falsifiable, must be false.
I resolve this contradiction by sacrificing physicalism and saying that matter must be observable. That does not mean observable by the naked eye, or that our senses are somehow infallible, both of which are strawmen that have nothing whatsoever to anything I've said.