It's a kitchen illustration. It completely demolishes Marx in just a couple paragraphs. What more do you ask for!?

Heinlein goes on to define Value a bit more to make his point, but I can't be assed to go find the quote again. But his point here is that effort is worthless and only the result of the effort matters. But it's such a joke of a point that I'd have assumed it was satire, if not for the fact that nothing else about the book is satire.