I Direct Monsieur to Diderot

Denis Diderot, French philosopher and editor/writer of the Encyclopédie, has some excellent things to say about painting.

Go, my friend, into a studio, and watch an artist at his work. If you see him arranging his tints and half-tints very carefully all round his palette, or if a quarter of an hour's work has not disturbed all this, you may boldly say that that artist is cold by temperament and will never produce any great work. He is like a heavy, pedantic scholar, who, when he wishes to quote a passage, mounts up his ladder and takes down the author he wants, opens the book, and, sitting down to his desk, copies out the passage, then mounts up his ladder again and replaces the volume. Those are not the ways of genius. The artist who has a strong feeling for colour sits before his canvas with his eyes fixed on it, his mouth open, his breath comes quick, his palette is in a state of chaos. And in this chaos he plunges his brush, and out of it he brings his creations—birds with all their varied plumage, flowers with their velvety texture, and the many-tinted foliage of trees, and the blue depth of sky, and the misty vapours that float therein, and the animals with their soft fur, and different markings, and their fiery eyes. He gets up and stands a little way off from his easel to look at his work ; and then he sits down again and you see appear under his touch the human form, drapery, cloth and velvet, damask and taffety, muslin, linen, or coarser stuff ; or you may see the ripe yellow pear dropping from the tree, or the unripe cluster's of grapes on the vine....

But what is the use of all these principles if taste is a capricious thing and if there is no eternal unchangeable law of beauty ?

If taste is merely a matter of caprice, if there is no law of beauty, whence come those delicious emotions which rise suddenly and involuntarily and tumultuously from the depths of our being, which loosen or tighten our heart-strings and force tears of joy, grief and admiration from our eyes at the sight of some grand physical phenomenon, or the hearing of some lofty moral trait of character? Begone, sophist, you will never persuade my heart that it did wrong to beat quicker, nor my emotions that they ought not to have been deeply stirred.

The true, the good, and the beautiful are very nearly connected. Add to either of the first two qualities some rare and striking circumstance and the true will be beautiful and the good will be beautiful.

Diderot, as the consummate encyclopaedicist, has a rather devotional wikipedia page, and was also the source for some excellent quotes:

No man has received from nature the right to command his fellow human beings.

In order to shake a hypothesis, it is sometimes not necessary to do anything more than push it as far as it will go.

It is very important not to mistake hemlock for parsley, but to believe or not believe in God is not important at all. (Darn. A point I've honestly thought was one of my better insights.)

Let us strangle the last king with the entrails of the last priest.

The philosopher has never killed any priests, whereas the priest has killed a great many philosophers.

My ideas are my whores.

Pithy sentences are like sharp nails which force truth upon our memory.

When superstition is allowed to perform the task of old age in dulling the human temperament, we can say goodbye to all excellence in poetry, in painting, and in music.

The best mannered people make the most absurd lovers.

You have to make it happen.