Since what the painter puts onto his canvas is visible to the eye, it will generally represent or suggest some form in nature. So the painter is a student of nature. But not in the same way as the botanist who studies the forms of trees and plants which grow above the ground, or the geologist who explores the secrets of the earth below the ground. These we call scientists or scientific students, because the object of their study is exact knowledge of nature. They address themselves directly to our _intellects_ and teach us to _know_ the _facts_ of nature accurately; but the painter appeals first to our _sense of sight_ and helps us to _feel_ more deeply the _beauty_ of the visible world.