Since ancient times, scholars have recognized the paradox of political power: power is necessary to enforce principles of just conduct, but power also renders favoritism and arbitrary action likely. Quis Custodiet Ipsos Custodes? Almost universally, this question has been pursued within a closed-system scheme of analysis. In contrast, we address this question within an open-system scheme of analysis, and explore some of the analytical differences that arise. In short, no resolution of the paradox is possible, for neither political entrepreneurship nor the crooked timber of humanity will allow it. Within open systems of creative and entrepreneurial action, freshness is continually injected into society, including new forms and uses of power. The challenge that the paradox of power presents for political economy is not to subdue it, which is impossible, but is to learn to live with it in a generally productive manner.