Is the first law of thermodynamics whatever we say it is? If that's how you want to phrase it, then again, this is a useless discussion. All you're really say

Is the first law of thermodynamics whatever we say it is? If that's how you want to phrase it, then again, this is a useless discussion. All you're really saying is that the literal English words and sentences we use to define something are human constructs. That's so obviously true.