According to Sherlock Holmes, "If you eliminate the impossible, whatever remains, however improbable, must be the..."

The story behind the answer

Truth. Holmes’s maxim is: “When you have eliminated the impossible, whatever remains, however improbable, must be the truth.” By ruling out explanations that cannot be, the lone survivor—no matter how unlikely—represents reality.

Arthur Conan Doyle gives Holmes this line in The Sign of Four (1890), and Holmes applies it throughout his cases. Though often called “deduction,” it’s closer to abductive reasoning: inferring the best explanation from limited clues. It pairs well with Occam’s Razor (prefer the simplest sufficient explanation), but here the key step is exclusion of impossibilities. Memory tip: “Impossible out → improbable in → truth within.”