Although manipulation is neither rational persuasion nor coercion, a more precise definition remains elusive. Two main accounts have been offered. One characterizes manipulation as a form of trickery. The other characterizes manipulation as a form of non-coercive pressure. Each account properly identifies only a subset of intuitively clear cases of manipulation. That is, some instances of manipulation apparently involve pressure, while others apparently involve trickery. Yet trickery and pressure seem distinct, so it is puzzling how they could be instances of (...) the same phenomenon. This puzzle can be solved once we recognize that manipulative pressure only works if the target acts akratically. This fact provides the basis for a unified account of manipulation as the attempt to get someone to make a mistake. (shrink)