The night is even more richly coloured than the day...If only one pays attention to it, one sees that certain stars are citron yellow, while others have a pink glow or a green, blue and forget-me-not brilliance. And without my expiating on this theme, it should be clear that putting little white dots on a blue-black surface is not enough.

∆ Vincent van Gogh, letter to sister, September 1888