A 7½-head figure, in which the length of the head serves as a basic unit of measurement, is the standard of proportions used in most realist schools and the one I taught my students in Florence. It’s important to keep in mind that the bodies of 99 percent of the world’s population don’t follow these rules; we all come somewhere close. Most adults are approximately 7 to 7½ heads high. In comparison, a toddler is approximately 4 heads high.