Science is different from older ways of using reason to understand the world because of its connection with the arts, in the sense of mimesis. The Greeks tried to explain things in the world, or to prove things about it. But science explains or proves only pragmatically and indirectly, because scientific understanding is not itself either explanation or proof: it is image, likeness, imitation.
The beginning of science is the principle that things which behave alike, are alike—even at disparate scales, under disparate circumstance, or for disparate ends. Either one is a version of the other, or both are by the same law. Gravity alike draws moon to apple and apple to moon; selection produces the artificial breed and the natural species; circulating information knots into systems like ecologies and minds.
Science is not a form of art; but no society has ever produced a scientific discovery unless its arts were already mature. The periods of Muslim scientific discovery were also periods of toleration for the representative arts—to explain the pulmonary circulation, Ibn an-Nafis had to draw a diagram. A scientist does not have to be an artist, nor does an artist does not have to be a scientist; but philistine scientists and superstitious artists are not pure, but lazy. Their countries are separate but not independent—they have different climates, but the same atmosphere; different shores, but the same sea beyond.
Brunelleschi, as a painter, created perspective, and mathematicians caught up with projective geometry. Chemists created new pigments and Impressionists, who saw the world in "patches of color," saw a new world.
More characteristically, the sciences of anatomy and natural history were created by, and still depend on, artists. The work of the anatomist is to reconcile a body, a continuous and not always clearly differentiated mass of cells, with the Body; the work of the naturalist, to reconcile the adaptive and adapting ramifications of a common descent, with a scheme of Species; but the human Body, the animal Species, are abstractions made by art—anatomical drawings exhibit the plan of the Body, naturalists' drawings exhibit the scheme of the Species, to show what is meant by the name before embodiment.
Leonardo called himself a the disciple of experience; Galileo looked to the book of nature; the formulations are interchangeable because arts and sciences are vulnerable to the same danger of self-regard. Original art is original not by breaking with tradition, but because it returns to the "master of masters," to nature; and original science is not done by pressing on with the great questions in hand, but by looking to nature, not to force an answer, but to find the right question.