John Berger. The art of seeing (№ 397479)

What distinguishes oil painting from any other species of painting is its ability to render the tangibility, texture, luster, density that it represents. For oil painting real is what you can touch. Its ability to create illusions much more significant than the sculpture, although the image on the canvas is two-dimensional - in fact, an oil painting offers the viewer objects that have color, texture and temperature, occupies a place in space and (it is implied) filling the whole world.