The real story

The underlying sentiment is plausibly Edison's, but the exact wording and number are unverifiable. The earliest documented source is the 1910 biography "Edison: His Life and Inventions" by Frank Lewis Dyer and Thomas Commerford Martin, where associate Walter S. Mallory recalled Edison saying: "Results! Why, man, I have gotten a lot of results! I know several thousand things that won't work." Mallory's recollection was recorded years after the actual conversation, making precision impossible. The "10,000" figure and the polished "I have not failed" framing are later elaborations that grew across subsequent retellings. The concept is consistent with Edison's known views, but the exact modern wording cannot be verified against a primary source.