so much
Note to the Nature of Wealth by John Ruskin

Price has already been defined (pp. 214, 215) to be the quantity of labour which the possessor of a thing is willing to take for it. It is best to consider the price to be that fixed by the possessor, because the possessor has absolute power of refusing sale, while the purchaser has no absolute power of compelling it; but the effectual or market price is that at which their estimates coincide.