A sketch will not serve more than one state of mind & will not serve to drink at again & again — in a sketch there is nothing but the one state of mind — that which you were in at the time.

Painting is a science, and should be pursued as an inquiry into the laws of nature. Why, then, may not landscape painting be considered as a branch of natural philosophy, of which pictures are but the experiments?

A sketch will not serve more than one state of mind & will not serve to drink at again & again — in a sketch there is nothing but the one state of mind — that which you were in at the time.

I never saw an ugly thing in my life.

It will be difficult to name a class of landscape in which the sky is not the key note, the standard of scale, and the chief organ of sentiment.

The world is wide; no two days are alike, nor even two hours; neither were there ever two leaves of a tree alike since the creation of the world; and the genuine productions of art, like those of nature, are all distinct from one another.

I never saw an ugly thing in my life: for let the form of an object be what it may - light, shade, and perspective will always make it beautiful.