Why could “the danger of lying in bed” be considered a personal essay?

“The Danger of Lying in Bed” takes a personal experience and connects it to something more general. One issue Twain explores is human gullibility—people’s tendency to accept something without looking at its underlying assumptions. He uses the idea of the train travel insurance as the symbol for carrying this thought and analysis. He discusses the obviously silly idea about how lying in bed is more dangerous than traveling as satire to show how people can use statistics to support even the most ridiculous ideas.

Ultimately, Twain’s satirical essay shows people that they shouldn’t accept everything they are told. Twain starts with what may or may not be an actual personal experience of traveling by train and being asked if he wants to purchase traveler's insurance. He uses it to develop a satirically logical conclusion that people are less likely to die while traveling by train than while sleeping at home. He includes actual research and data to support his satirical views.

Qualities that indicate this is a personal essay include opening with an anecdote, reflecting on a personal experience, and commenting on an issue—in this case, human gullibility.