This is kind of making me think that nothing has intrinsic value. A pound of Wagyu beef and a pound of chuck steak have vastly different prices but essentially the same nutritional value. The exact same house in one neighborhood could cost three times as much as in another neighborhood. Store brand or generic drugs cost less than brand name drugs with the same active ingredients.
I am not a lawyer, accountant, or economist (which is probably clear from my post). But it seems to me that the "value" of anything is what someone else is willing to pay for it, from game-used bats to stocks to houses. The difference with stocks is that there is an active market that continually sets a price. If you want to sell a stock, you can't just set your own price on a BST board, or consign it to an auction with a reserve. But the upside is that stocks are immediately sellable when you want to sell them.
And regarding a shared belief system, cash itself is based on that. A $1 bill and a $100 bill have the same material value, but we have all agreed that a $100 bill is worth 100 times more that a $1 bill (not that anyone uses cash anymore).
Those are my simplistic economic theories after midnight
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