Aristotle was fascinated with how persuasion works, and one of his most basic ideas — one many of us learned in middle school — is that true persuasion requires three ingredients: pathos (emotion), logos (logic) and ethos (credibility). He also found that the most persuasive arguments relied twice as much on emotion as on logic and credibility combined. The best TED Talks follow this formula. So does the best marketing. Need proof? Take 60 seconds to re-watch Apple’s 2013 Christmas TV spot for the iPhone. Now compare and contrast with your own marketing messages.