It is difficult to recall any one Bob Ross painting. Mountain Waterfall looks a lot like Mountain Retreat, which looks a lot like Brown Mountain before it and Autumn Mountain before that. As the host of The Joy of Painting, an American television tutorial that ran for 31 seasons between 1983 and 1994, Ross painted over 400 variations on the theme. His was an oeuvre of quantity—a prolific series of boreal mirages, like New Age desktop wallpapers. “Talent is a pursued interest,” he once said.

Ross (pictured, holding a baby raccoon) was the first to admit that his paintings comprised lots of what he called “happy accidents.” He encouraged viewers to make them too, and not to worry. Mistakes could be turned into trees, and Ross saw all trees as happy and little. “And don’t mak...