When Van Gogh wrote to his
brother Theo in March 1889, to address the concern doing the rounds that «instead of eating enough and at regular times, I
kept myself going on coffee and alcohol», he didn't deny it, but instead claimed it was needed for his
work: «I admit all that, but all the same it is true that to attain the high yellow note that I attained last summer, I really had to be pretty
well keyed
up.