The explosion of conspiracy theories accompanying the mass killing in Las Vegas can be seen all over the Internet.The theories and their rationals range from the absurd, such as “a 64-year-old man could not have moved 10 bags up to his room alone” to somewhat sophisticated analysis of cell phone recordings that claim to find evidence of two shooters. I have not seen any convincing evidence that requires a conspiracy to explain the mass murder. I use Occam's razor to winnow out the theories. That is, when given two explanations, the preference should be given to the simpler, less...