Machinery runs according to the laws of mechanics and not according to the moral law. This is not to say that the laws of mechanics are immoral, but simply that they are non-moral. Now the main principle of mechanical invention is the elimination of waste energy. Of two machines doing the same work, that is the better which costs less to run. This is the same as saying that the better machine is better designed for its purpose; for the purpose of machinery is to reduce the costs of production. The chief cost of production is human labour. Even the cost of materials is chiefly made up of the cost of human labour. Stone would be as cheap as dirt if it could be dug as easily. Petrol would be as cheap as water if it came down as rain. It is always labour which costs money. I leave out of consideration here the question of bank interest and interest on money borrowed. If interest is not in some way payment for effort it is usury, and as such an unjust charge, something for nothing, a thing to be abolished as a thing ruinous to society. It is labour which costs money and it is to Save the cost of labour that machinery has been invented and its use spread throughout the world. Tools are not machines in the common sense of the word. A thing is a tool when it helps. A hammer helps a man to get a nail into a wall. A chisel helps a man to cut stone or wood.