On Picket Duty. In a series of articles in the London Commonweal, Dr. Edward Aveling, newly-fledged disciple of Karl Marx, discusses economic questions. He concludes each article with what he calls a concise definition of each of the terms mentioned. These two definitions stand side by side. Natural object—that on which human labor has not been expended; Product—a natural object on which human labor has been expended. A product, then, is something on which human labor has not been expended on which human labor has been expended. Curious animal, a product! No wonder the laborer is unable to hold on to it. More slippery than a greased pig, I should imagine. But this is a scientific definition, and I suppose it must be true. For its author, Dr. Aveling, is a scientist, and the subject of his articles is Scientific Soc...