modity irrespective of its exchange-value (Marx knows of only two kinds of value: use-value and exchange-value, and wherever he says simply "value" he means exchange-value), the statement contains some important inaccuracies.
To begin with, Marx never forgets the "purposes and necessities" for which production is undertaken. Quite the reverse: this thought is ever present in his mind, and it is due to this very fact that Marx did not fall into some of the grievous errors into which his critics, particularly the "moderns," have fallen. These gentlemen talk of the "psychological" motives of exchange as the cause and measure of value, all the time forgetting that before a commodity can be exchanged it must be produced, and that there must therefore be, first of all, "psychological" motives of production which ought to be of some considerable interest. Not so with Marx. He always remembers that in our capitalistic system (be it remembered: Unlike his critics, Marx never talks of eternity, but of the present capitalistic system) production is undertaken for the purpose of profit. This implies two things: First, that the producer does not produce the thing for its use-value, he does not give a snap for that, it is absolutely useless to him, and he will just as soon manufacture chewing-gum as Bibles.—And, second, that he knows in advance, or at least thinks he knows, the value of the product he is going to produce; in other words, he knows that the value of his product will depend on something more substantial and rational than the whimsical "desire" of the prospective purchaser based on some individual, "psychological" motivation. And this knowledge on the part of Marx of the purposes of capitalistic production had something to do with his abstracting from the useful qualities of the particular commodities when examining their exchange-value, as well as with his refusal to follow Böhm-Bawerk's advice to arrive at the laws of exchange-value by way of an examination of the "psychological" motives of exchange.
It is also somewhat inaccurate to say that, according to
