Abstract: Nietzsche and Hume agreed that desire drives all human action and practical reasoning. This shared view helped them appreciate the continuity between human and animal motivation, and set them against a long tradition of rationalist rivals including Kant and Plato. Kantians like Christine Korsgaard argue that reflectively endorsement and rejection of options presented by desire demonstrates reason's ability to independently drive reasoning and action. In Daybreak 109, Nietzsche provides a simpler Humean explanation: reflective endorsement and rejection involve reflecting on one desire from the viewpoint of another.