In his 1920 book My Second Country, political theorist and Francophile Robert Dell quotes Ernst Renan as saying:
The only thing that gave me any conception of infinity was human
In 1915, five years before he published My Second Country, Dell had attributed that quote to a "great astronomer." It read:
It isn't the stars that give me an idea of infinity―it is man's
The problem with this quote is that the Ernst Renan whom Dell quotes in My Second Country was not an astronomer, but rather, a French philosopher, who apparently had an interest in the idea of an infinite universe. The saying that Dell misremembers is however, one that Renan actually wrote, in his book titled Dialogues et Fragments Philosophiques. It said:
"La bêtise humaine est la seule chose qui donne une idée de l'infinie."
(Human stupidity is the only thing that gives an idea of the
Going back even further in time, Guy de Maupassant's 1880 book Des Vers has a quote from a letter by Gustav Flaubert which reads:
"Ce pendant, qui sait? La terre a des limites, mais la bêtise humaine
est infinie!" (But who knows? The earth has limits, but human
stupidity is infinite!)
Here we have Guy de Maupassant, like Dell, misremembering a quote almost word-for-word. Flaubert's actual historical text from his letters reveals the saying as:
"Aujourd'hui je sais qu'il n'y a pas de limites à la bêtise
humaine―qu'elle est infinie." (Today I know that there is no limit to
human stupidity―it is infinite.)
Further complicating matters is the attribution in 1904 by British member of Parliament John Morley, of the quote not to Renan or Flaubert, but to a third Frenchman―Voltaire―from his Works of Voltaire. A Contemporary Version Critique and Biography. In it, Voltaire says:
"Ce n'est pas l'immensité de la vôute étoilée qui peut donner le plus
complétement l'ideé de l'infini, mais bien la bêtise humaine." (It is
not the starry sky that can give the most complete idea of the
infinite, but human stupidity.)
That quote, like all the others, sounds a lot like the one attributed to Einstein. And yet, if Morley's 1904 book is correct, it was said by Voltaire over 100 years before Einstein was even born. With all of these different variations, one can't help but wonder: from where did this quote actually originate, and from whom?
In the end, be it Einstein, Renan, Flaubert or Voltaire, I believe that the occasional reappearance of this saying in various historical texts—all quite similar in meaning but by different authors—is strong evidence that the saying itself might just have been a standard cliché of the period, rather than something that one person singularly said on their own.