It was the American physicist Albert Michelson (the creator of the beautiful Michelson interferometer design which enabled very precise measurements of the speed of light) who said "it seems probable that most of the grand underlying principles have been firmly established . . . An eminent physicist remarked that the future truths of physical science are to be looked for in the sixth place of decimals."

Subsequently, the sentiment of this statement has been misattributed to Lord Kelvin.