This document summarizes a presentation given by Theo Mandel on using UX design powers for good or evil. Mandel discusses how UX design can be used persuasively through techniques like reducing cognitive load and increasing consistency, but also warns about "dark patterns" that use deception. He provides examples of both persuasive design practices that help users as well as "evil" designs like hidden costs and tricks to keep users from canceling subscriptions. The presentation emphasizes the importance of using design for good by being transparent and having the user's interests in mind.