The document is a presentation on applying Lean principles in the context of human behavior and decision-making. It discusses cognitive biases and irrational tendencies that influence human reasoning. It then explains how Lean can help individuals and organizations overcome these biases to make more rational decisions through processes like validating hypotheses, gathering customer feedback, and embracing experimentation. In the end, Lean is presented as a way for irrational people to make rational decisions through these evidence-based practices while still maintaining good interpersonal relationships.