More knowledge can divide us

Paradoxically, the result of having so much more shared knowledge [with the spread of printing] was increasing isolation along national and religious lines. The instinctual shortcut that we take when we have "too much information" is to engage with it selectively, picking out the parts we like and ignoring the remainder, making allies with those who have made the same choices and enemies of the rest.

Nate Silver, The Signal and the Noise: Why So Many Predictions Fail—But Some Don't (Penguin Books, 2015) (orig., pub., 2012), p. 3

Keep learning!

Let me advise you to pursue the same course through life, recollecting that, even as practitioners, you must still be students. Knowledge is endless, and the most experienced person will find that he has still much to learn.

Sir Benjamin Collins Brodie, speech to students at St. George's Hospital, London, in 1850, quoted in Bill Hayes, The Anatomist: A True Story of Gray's Anatomy (New York: Ballantine Books, 2008), ch. 5 (citing The Works of Sir Benjamin Collins Brodie, vol. 1 (London: Longman et al., 1865)).

Education for a Highland rebel

"A man kens little till he's driven a spreagh of neat cattle (say) ten miles through a throng lowland country and the black soldiers maybe at his tail. It's there that I learned a great part of my penetration. And ye need nae tell me: it's better than war; which is the next best, however, though generally rather a bauchle of a business. Now the Gregara have had grand have had grand practice."

"No doubt that's a branch of education that was left out with me," said I.

"And I can see the marks of it upon ye constantly," said Alan. "But that's the strange thing about you folk of the college learning: ye're ignorat, and ye cannae see 't. Wae's me for my Greek and Hebrew; but, man, I ken that I dinnae ken them—there's the differ of it. Now here's you. Ye lie on your wame a bittie in the bield of this wood, and ye tell me that ye've cuist off these Frasers and Macgregors. Why? Because I couldnae see them, says you. Ye blockhead, that's their livelihood."

Robert Louis Stevenson, Catriona (1892), pt. I, ch. 11

Facts change: get used to it

We have to begin actually educating ourselves and our children to recognize that knowledge will always be changing and showing the regularities behind how these changes can happen. More important than simply learning facts is learning how to adapt to changing facts.

Samuel Arbesman, The Half-Life of Facts: Why Everything We Know Has an Expiration Date (New York: Current, Penguin USA, 2012), ch.10

The curse of knowledge leads to bad writing

The better you know something, the less you remember about how hard it was to learn.

The curse of knowledge is the single best explanation I know of why good people write bad prose. It simply doesn’t occur to the writer that her readers don’t know what she knows—that they haven’t mastered the patois of her guild, can’t divine the missing steps that seem too obvious to mention, have no way to visualize a scene that to her is as clear as day.  And so she doesn’t bother to explain the jargon, or spell out the logic, or supply the necessary detail.

Steven Pinker, The Sense of Style: The Thinking Person's Guide to Writing in the 21st Century (New York: Viking, 2014), ch. 3 (footnotes omitted)

It can be better not to rely on memory!

[R]ather than relying on memorizing often out-of-date facts, and still usually only half-remembering them, embrace the idea that we have the Internet at our disposal, with search engines at our fingertips that enable us to search for any fact we need anytime.

This is already happening. A recent paper in the journal Science finds that people are coming to rely more and more on search engines rather than their own memory. When the study was released, many people fretted about this and how it is hurting our brains and making us dumber. While this is certainly a common argument, I took away the opposite conclusion. Paradoxically, by not relying on our own memories, we become more likely to be up-to-date in our facts, because the newest knowledge is more likely to be online than in our own heads.

Samuel Arbesman, The Half-Life of Facts: Why Everything We Know Has an Expiration Date (New York: Current, Penguin USA, 2012), ch. 9 (citing Betsy sparrow, Jenny Liu & Daniel M. Wegner, "Google Effects on Memory: Cognitive Consequences of Having Information at Our Fingertips," Science, vol. 353, no. 6043 (2011), pp. 776-78)

A key professional habit could be wrong--surgeon changes hand-washing routine

The ten-minute scrub was one of the earliest rituals I had learned, and I thought that it was essential in surgical antisepsis, a crucial step in preventing my patients from developing debilitating postoperative infections. I had believed that my dedication to this operating room rite made me a good and responsible surgeon, but the research contradicted that belief. Suddenly my blind trust in the practice seemed almost foolish.

Pauline W. Chen, Final Exam: A Surgeon's Reflections on Mortality  (New York: Alfred A. Knopf, 2007), p. 97. (After years of scrubbing for ten minutes with brushes, Chen read CDC guidance that recommended five minutes and said soft sponges were as useful as brushes.)

Easier to spread error than check facts

[T]he reason these errors spread is that it's a lot easier to spread the first thing you find, or the fact that sounds correct, than to delve deeply into the literature in search of the correct fact. 

Samuel Arbesman, The Half-Life of Facts: Why Everything We Know Has an Expiration Date (New York: Current, Penguin USA, 2012), ch. 5

Pinker on writing to your audience

Every audience is spread out along a bell curve of sophistication, and inevitably we’ll bore a few at the top while baffling a few at the bottom; the only question is how many there will be of each. . . . The key is to assume that your readers are as intelligent and sophisticated as you are, but that they happen not to know something you know.

Steven Pinker, The Sense of Style: The Thinking Person's Guide to Writing in the 21st Century (New York: Viking, 2014), ch. 3

Some false beliefs are really wrong

[W]hen people thought the earth was flat, they were wrong. When people thought the earth was spherical, they were wrong. But if you think that thinking the earth is spherical is just as wrong as thinking the earth is flat, then your view is wronger than both of them put together. 

Isaac Asimov, quoted in Samuel Arbesman, The Half-Life of Facts: Why Everything We Know Has an Expiration Date (New York: Current, Penguin USA, 2012), ch. 3

Sherlock Holmes's attic theory of knowledge

His ignorance was as remarkable as his knowledge. Of contemporary literature, philosophy and politics he appeared to know next to nothing. . . . My surprise reached a climax, however, when I found incidentally that he was ignorant of the Copernican Theory and of the composition of the Solar System. That any civilized human being in this nineteenth century should not be aware that the earth travelled round the sun appeared to be to me such an extraordinary fact that I could hardly realize it.     

"You appear to be astonished," he said, smiling at my expression of surprise. "Now that I do know it I shall do my best to forget it."     

"To forget it!"     

"You see," he explained, "I consider that a man's brain originally is like a little empty attic, and you have to stock it with such furniture as you choose. A fool takes in all the lumber of every sort that he comes across, so that the knowledge which might be useful to him gets crowded out, or at best is jumbled up with a lot of other things so that he has a difficulty in laying his hands upon it. Now the skilful workman is very careful indeed as to what he takes into his brain-attic. He will have nothing but the tools which may help him in doing his work, but of these he has a large assortment, and all in the most perfect order. It is a mistake to think that that little room has elastic walls and can distend to any extent. Depend upon it there comes a time when for every addition of knowledge you forget something that you knew before. It is of the highest importance, therefore, not to have useless facts elbowing out the useful ones."     

"But the Solar System!" I protested.    

"What the deuce is it to me?" he interrupted impatiently; "you say that we go round the sun. If we went round the moon it would not make a pennyworth of difference to me or to my work."

Sir Arthur Conan Doyle, A Study in Scarlet, ch. 2 (first published 1887)