> You are using marginal utility value theory. Parent comment is using labor value theory.
Yes, I'm aware. This is precisely why I'm stating the prior comment to be "absolutely wrong". Marginal utility is a substantially valid model, LTV is not.
> In fact, there are also other value theories in economy. It's a mostly philosophical choice, and like other philosophical choices, it's not possible to accuse one of them of being wrong.
Sure it is. These aren't theories in a normative sense, they're models of causality for manifest phenomena. They're closer to scientific theories than they are to philosophical axioms. LTV simply doesn't bear out with observation.