Epstein’s key point is that the ten-thousand-hour idea must be understood as an average. For example, both he and I discuss the same study by the psychologist K. Anders Ericsson that looked at students studying violin at the elite Music Academy of West Berlin. I was interested in the general finding, which was that the best violinists, on average and over time, practiced much more than the good ones. In other words, within a group of talented people, what separated the best from the rest was how long and how intently they worked. Epstein points out, however, that there is a fair amount of variation behind that number—suggesting that some violinists may use their practice time so efficiently that they reach a high degree of excellence more quickly. It’s an important point. There are seventy-three great composers who took at least ten years to flourish. But there is much to be learned as well from Shostakovich, Paganini, and Satie.