 The earliest known mention of this idea occurs in Douglas Hofstadter's 1985 book "Metamagical Themas", where Hofstadter states

This sequence of six nines is sometimes called the "Feynman point", after physicist Richard Feynman, who allegedly stated this same idea in a lecture.It is not clear when, or even if, Feynman made such a statement, however; it is not mentioned in published biographies or in his autobiographies, and is unknown to his biographer, James Gleick.is conjectured to be, but not known to be, a normal number.