Every purchase and sale hinges on the value or worth of the goods or services in question. Before we buy a loaf of bread for $1 or a house for $100,000, we want to be sure that it is worth the price, that it has the necessary value. But what sort of value is this, what exactly does it consist in? Value is not all of one kind. There are numerous different kinds of value. For example, there is aesthetic value, which is the special value we attribute to things of beauty, such as the music of Mozart or the poetry of Shelley. There is utility or use value, which is the kind of value we attach to things that we can use as means to some end we want to achieve: a screwdriver might have little use value to someone engaged in writing poetry, but quite a lot to someone building a house. There is emotional or sentimental value, which is the value we attach to particular objects associated with loved ones, or with special memories. The house that I grew up in will usually mean a lot more to me than to others for whom it is just another house; a house that I have built with my own hands will mean more to me emotionally than one I buy ready-made. There is moral value, which is the special value we see in virtue, like courage, or honesty, or generosity. There are values of personal preference, or personal taste: some people like chocolate-chip ice cream, others don't. And then there is economic value.
Economic value is simply exchange value. The exchange value of any item is what someone is prepared to give in exchange for it. The exchange value of a house, for example, is the highest price that some actual person is willing and ready to pay for it. That is, the economic value of the house is just whatever price the buyer and seller agree on. If someone is pre-