How can we prove that?
Technologies working can test physical predictions. They cannot test the metaphysical claim that facts have truth independent from common language. Simply asserting that they do is the realism that I am disputing.
Also, the proposition in question is made in a certain language, and is not true in all possible languages.
The proof that the proposition exists can be found in the countless references and papers referencing it, including Einstein's original 1905 paper. You can find the Wikipedia page on mass-energy equivalence here[0] and the paper here[1].
And you were talking about language, not conceptual frameworks. Obviously one can imagine conceptual frameworks where E=MC^2 is not true, but your argument was that facts cannot exist and cannot be proven outside of the language with which they are expressed, which is obviously false because observation, experimentation and science are not expressed entirely with language.
>Technologies working can test physical predictions. They cannot test the metaphysical claim that facts have truth independent from common language.
Yes they can, because if facts didn't have truth independent from common language, the technology wouldn't work, or rather, would work differently depending on the language of the user. This obviously isn't the case. We can observe that the universe, made up of stars and planets that don't have language, nevertheless obey the physical laws that we express in language. We can observe that animals which don't have language behave in ways we can describe, and obey physical laws they can't comprehend.
>Also, the proposition in question is made in a certain language, and is not true in all possible languages.
It is. It was true when Einstein wrote it in German, it was true before he wrote it down, it remained true when it was translated into English, it's true in Esperanto, Dutch, Klingon, any language you prefer, because language doesn't define reality, it only describes it. Rename it Q=XZ^01 and it still describes the same fundamental and immutable fact about reality. Write it upside down and it still works the same.
[0]https://en.wikipedia.org/wiki/Mass%E2%80%93energy_equivalenc...
If facts have truth independent from common language, where do those facts exist, and how do you define existence in this context?
As an example, are you hinting at the existence of facts and truths that are somehow different from the easier definition of formal truths which hold in an assumed axiomatic framework, as happens in mathematics, which itself is a framework of language?
shred it into pieces ! lmao