Category Archives: Sophonisba Breckinridge

You Don’t Have to Know Everything. You Just Have to Know Where to Find It

Albert Einstein? Samuel Johnson? Sophonisba Breckinridge? John Brunner? Anonymous?

soph09Dear Quote Investigator: The depth and breadth of information available on the internet is wondrous. Here are three examples from a family of pertinent sayings I came across recently:

1) I don’t need to know everything; I just need to know where to find it, when I need it.
2) Never keep anything in your mind that you can look up.
3) Never memorize what you can look up in books.

These sayings express a fundamental insight into this age of vast knowledge bases and high-speed networks. The words were credited to Albert Einstein, but I cannot find any precise reference. There so much junk and misinformation about quotations. The prevalence of inaccurate data makes it harder to find correct information. Can you trace this general saying?

Quote Investigator: These quotations were not listed in the key reference work “The Ultimate Quotable Einstein” from Princeton University Press. 1 Also, QI has not located any evidence of an exact match in the words written by the illustrious scientist.

Einstein did make a remark in 1921 that was conceptually related to the quotation. While visiting Boston he was asked whether he knew the value of the speed of sound, and he demurred: 2

He was asked through his secretary, “What is the speed of sound?” He could not say off-hand, he replied. He did not carry such information in his mind but it was readily available in text books.

Einstein’s remark was about a single fact; hence, it differed from the statement under investigation. Nevertheless, it was possible to generalize and reformulate his comment to apply to the wider set of knowledge available in books. Indeed, another version of Einstein’s response that was published in 1947 was closer to the sayings being examined. (Details are given further below.) Hence, the modern expressions may have evolved from Einstein’s comment in 1921.

The idea presented in the quotation does have a long history before the computer age. Here are additional selected citations in chronological order.

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  1. 2010, The Ultimate Quotable Einstein, Edited by Alice Calaprice, Princeton University Press, Princeton, New Jersey. (Verified on paper)
  2. 1921 May 18, New York Times, Einstein Sees Boston; Fails on Edison Test: Asked to Tell Speed of Sound He Refers Questioner to Text Books (Special to The New York Times), Quote Page 15, New York. (ProQuest)