This eBook is the fourth in a series and serves as a companion and guide to the pioneering book, Understanding Laughter and Humor: Why We Laugh, Why We Don't, and Why It Matters, published by Palgrave Macmillan. Inside, readers will learn how to use the Mutual Vulnerability Theory of Laughter to comprehend and appreciate cognitive humor?instances when memory, problem-solving, and decision-making abilities fall short of that which might be considered "normal." Such shortcomings often serve as stimuli for spontaneous bouts of laughter, as well as material used for humor and comedy, and this eBook will explain exactly why this should be.