Today's guest blogger is Vincent Van Gogh.

To be good – many people think that they’ll achieve it by doing no harm – and that’s a lie, and you said yourself in the past that it was a lie. That leads to stagnation, to mediocrity. Just slap something on it when you see a blank canvas staring at you with a sort of imbecility.

You don’t know how paralysing it is, that stare from a blank canvas that says to the painter you can’t do anything. The canvas has an idiotic stare, and mesmerises some painters so that they turn into idiots themselves.

Many painters are afraid of the blank canvas, but the blank canvas is afraid of the truly passionate painter who dares – and who has once broken the spell of ‘you can’t.’

Life itself likewise always turns towards one an infinitely meaningless, discouraging, dispiriting blank side on which there is nothing, any more than on a blank canvas.

But however meaningless and vain, however dead life appears, the man of faith, of energy, of warmth, and who knows something, doesn’t let himself be fobbed off like that. He steps in and does something, and hangs onto that, in short, breaks, ‘violates’ – they say.

Let them talk, those cold theologians.

The text is from a letter to his brother, Theo, written in 1884, and quoted in the London Review of Books by Julian Bell, in a review of a new English edition of Van Gogh's complete letters.