The doctrine that some people hold that there is no such thing as pain, is very helpful in the training of the mind, although its truth may be questioned. If it is true that there is no such thing as pain, it can only be true in the sense that everything in this world is an illusion, it has no existence of its own, it does not exist in reality, compared with the ultimate reality that is. But when a person says that it is only pain which does not exist, but that joy exists and all other things exist, then he is wrong.