When we consider the four kingdoms -- the mineral, vegetable, animal kingdoms and mankind -- we see that not man alone but also every other being has the gift of expression. The rock expresses least and we feel least for it; we strike it and break it and quarry it. We make use of it in every way and we do not sympathize with it at all, because it does not speak to us; it tells us very little. We sympathize much more with the plant. We love it, we give it water, we tend it, and because it has more expression we care more for it. Among the stones there are some that speak more to us; the diamond, the ruby, the emerald we prize very much. We pay thousands of pounds for them; we are glad to have them, to wear them.