 Supertasks often lack a final or initial step. A famous example is the first of  Zeno’s Paradoxes,  the Paradox of the Dichotomy. The runner Achilles begins at the starting line of a track and runs ½ of the distance to the finish line. He then runs half of the remaining distance, or ¼ of the total. He then runs half the remaining distance again, or ⅛ of the total. And he continues in this way ad infinitum, getting ever-closer to the finish line (Figure 1.1.1). But there is no final step in this task.