The Importance of Marxism—(continued)

"For example: There are six customers in a shop, each of whom, shall we say, demands a tin of biscuits, and the shopkeeper has precisely six tins of biscuits to sell. What happens in these circumstances ?"I'm discussing the LTV with a non-marxist and I basically took this quote as a part of my reply. The reply I got was this:"The biscuit example is a stylized scenario. In the real world, a shop owner won't change his pricing policy based on the specific circumstances of one moment and try to clear the market at any point. He is perfectly willing to keep the biscuits as inventory in order to sell them later for a higher price, or to even throw them away rather than to lower the price until it clears immediately, so as to not destroy his total income down the way (or give customers the incentive to wait for the late-night sales).In reality, the shop owner bases his pricing on overall supply and demand dynamics. How much money is he willing to trade his biscuits for? In other words: what are the lowest costs plus profits he's willing to sell X amounts of biscuits (the supply curve)and at what price point are customers willing to buy the biscuit amount of X (the demand curve)?But even in a "Robinson Crusoe" economics example: there are 6 biscuits (and no way to make more) and 6 customers, each willing to buy one of the biscuits at up to price X. In that case supply and demand still determine most of the transaction: Supply is determined by the biscuit owners own opportunity costs (what is the biscuit worth to him if he doesn't sell it?) and demand is determined by the customers' willingness to buy a single biscuit. Of course we restricted the possibility to increase quantity artificially and ruled out competition. But supply and demand still matter. This market will clear. Either they are willing to pay what he asks for or not. It doesn't need to follow a Walrasian concept of equilibrium to be true. Equilibrium is simply a state in which nothing and all forces are at balance. Whether or not those biscuits will get sold at the end of the day, if nobody feels the need to act, that's an equilibrium." Anyone with more knowledge on the LTV who could argue against this?

Marx's theory was an attempt to explain the dynamics of capitalism, how labour is regulated and distributed in a market economy. It's not a theory of equilibrium price.