One morning, while sipping my coffee, I read a report in the newspaper that the researchers at a defense contractor had invented an entirely new kind of gun called a Peace Gun. When fired, the article said, the gun would retroactively undo acts of violence committed by anyone its bullets hit. These acts would actually be completely erased from the continuum, such that it was as if they had never occurred. Fresh cuts and bruises would disappear, old scars would vanish, lost appendages would suddenly have never been severed at all: this had all been independently documented and confirmed in multiple rounds of double-blind testing on both animal and human subjects. For those actually shot by the Peace Gun, of course, it was the same as being shot by any other gun, with many subjects additionally reporting a feeling of “spiritual dislocation.” During the press conference announcing their findings, the article said, the researchers stressed that they had not tested the gun on known murderers, and strongly advised against doing so. The gun, they said, according to the article, was best suited for use against “petty criminals and other small-time social disruptors.” They also stressed that they did not understand how the Peace Gun worked. “One morning, while sipping my coffee,”  the lead scientist was quoted as saying, “I suddenly got a terrible headache. My head felt split open by strange equations and formulas. These became the basis for the whole project.” It was an interesting article. I turned the page to the Sports section and read about a jockey that had been killed when his horse slipped on a greasy hot dog wrapper. Apparently, the article said, the wrapper had blown onto the track from the stands. I shook my head. So senseless. I sipped my coffee.