Let me sum up sympathy very quickly since you will probably never need to have anything other than a rough comprehension of how these things work. First, energy cannot be created or destroyed. When you are lifting one drab and the other rises off the table, the one in your hand feels as heavy as if you’re lifting both, because, in fact, you are. That’s in theory. In practice, it feels like you’re lifting three drabs. No sympathetic link is perfect. The more dissimilar the items, the more energy is lost. Think of it as a leaky aqueduct leading to a water wheel. A good sympathetic link has very
...more
