From Man, Economy, and State, with Power and Market — surrounding passage

There is no possible unit of happiness that can be used for purposes of comparison and, hence, of addition or multiplication. Thus, values cannot be measured; values or utilities cannot be added, subtracted, or multiplied. They can only be ranked as better or worse. A man may know that he is or will be happier or less happy, but not by “how much,” not by a measurable quantity. 17

“All action is an attempt to exchange a less satisfactory state of affairs for a more satisfactory one.”

The actor finds himself (or expects to find himself) in a nonperfect state, and, by attempting to attain his most urgently desired ends, expects to be in a better state. He cannot measure the gain in satisfaction, but he does know which of his wants are more urgent than others, and he does know when his condition has improved.