He Could Buy Food
Benny enjoyed the way the painting looked. His instincts advised him to buy it and assist Arthur simultaneously. He made Arthur an offer of $20 for the photograph. That would feed Arthur for a couple of days, and Benny thought he could make a modest gain off of it.
Arthur grinned, accepted the money, and went away cheerfully. Benny was under the impression that he understood what he was staring at, but once he saw the reality, he was completely mistaken.