Edwin Tenney Brewster, Natural Wonders
“ These turnings of plant or animal, toward the light or away from it, up or down, the heading up-stream of many fishes, and the necessity for crowding into cracks and corners of many insects and other small creatures, all these are called “tropisms.” Tropism is merely the Greek word for turning. I tell you the name, because we human beings who have speech, if we want to think about a matter, have to have a name for it to act as a handle for our minds to take hold of. ”
