An important debate in the current philosophy of wisdom is whether knowledge is necessary for wisdom. In this paper I argue that knowledge is necessary to explain wise actions. Towards this, firstly, I individuate two modal properties relevant for wise actions: (i) counterfactual robustness: an action performed in the actual world is wise only if it leads to or is constituted by the goals of living well in all nearby worlds; (ii) rational robustness: an action performed for the sake of (...) living well is wise only if, in all nearby worlds, when an agent has sufficient reasons to perform the action, she performs the action. Secondly, I argue that these two modal properties are best explained in terms of two central features of knowledge: (a) safety: if the agent knows that a certain action will help her successfully reach the relevant goal(s) of living well, or is constituted by those goal(s), then in all the nearby worlds, her belief that the action will help her successfully reach the goal is true; (b) stability: the agent's knowledge that the action will help her successfully reach the goal(s) of living well, or is constituted by those goals, entails that her belief that the action will help her successfully reach the goal(s), or is constituted by those goals, isn’t based on any reason that could easily have been defeated by misleading evidence. (shrink)