Our vision is weird

This video does a nice job of highlighting some weird aspects of human vision in just three minutes.


Link: https://youtu.be/0NPH_udOOek

This first oddness it mentions is the blind spot, a place on the retina devoid of imaging cells where the optic nerve (which is really a big bundle of nerves) meets the eye. This is even stranger than the video suggests, because the optic nerve doesn't just make contact there, it passes through the back of the eye so its various fibers can spread out across the retina and connect up with the light-sensitive rod and cone cells from the front.

This is true not just of human eyes but the eyes of all vertebrates -- fish, amphibians, reptiles, birds, and mammals, so you might suppose that there's some necessary reason for it. But it's not true of the eyes of a squid, octopus, or cuttlefish, that is, the cephalopods. Their optic nerves connect up to light-sensitive cells from the back, so there's no need for a blind spot.

So why don't vertebrate eyes work the same way? It's probably just another of several examples of evolutionary accidents, things that seems bizarre from an engineering standpoint but are what you'd expect given evolutionary development.

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Maybe Hillary Clinton should have taken Bill Maher's advice

From a late July episode of HBO's Real Time with Bill Maher, a six-minute segment of advice to Hillary Clinton about how to present herself. (Usual caution to those sensitive to naughty language: This is Bill Maher speaking on cable.)


Link: https://youtu.be/7hBnwPycFUQ

Clinton's lead in the popular vote is more than 2.5 million votes. A modestly higher Democratic turnout in three usually blue states would have given her the electoral vote as well. Maybe she should have followed Mather's suggestions. Anyway, they're reasonably amusing.

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Misinformation voters

For a long time people have talked about the problem of low-information voters, those who typically don't care all that much about politics, rarely watch the news, and rely on general impressions. To varying degrees this has probably been true of most voters in most places throughout the history of voting.

Lately I've been thinking about another group, people care a great deal about politics, devote a lot of time to talking and reading about it, and consider themselves very well-informed indeed despite the fact that a large part of what they think they know is demonstrably wrong at the level of objective fact. There have always been a lot of these folks as well, especially on the political extremes, but there may be cause to worry that this problem is getting a lot worse. Here's a two-and-a-half-minute example:


Link: https://youtu.be/9DEdpTIXuro

As multiple fact-check organizations across the political spectrum (and even Newt Gingrich) have pointed out, evidence shows that it's extremely unlikely (to put it charitably) that millions of non-citizens voted in last month's U.S. elections. It's also not true that California "allows it," and of course President Obama didn't tell illegal immigrants to vote. But clearly some people believe such nonsense, and they haven't made it up themselves; they're getting it from somewhere. Some of the misinformation even comes from president-elect's Twitter feed.

Of course, politicians have been known to lie, people to repeat rumors, and news media to get things wrong. But lately we've been seeing deliberately made-up, highly sensational fake new stories published on the professional-looking websites of what appear to be real news outlets. Some of the sites are owned by Americans, some of whom claim to be engaged in satire or shenanigans or social experiments meant to see just what people can be made to believe. (One admitted he targeted Trump supporters because they don't bother to fact-check.) Interestingly, a fair number of sites are owned by a group of well-educated entrepreneurial teenagers in Eastern Europe.

And we're not talking about some esoteric little backwater of the Internet. In the run-up to the latest election people on Facebook shared more links to deliberately fake news stories than to real ones from actual newspapers and networks,

Facebooks and Google have promised to look into doing something about fake news. (I would hope this means flagging the links as questionable rather than blocking them outright.) Legitimate news sources have also devoted time to informing people about the existence of fake news, and more generally, the media seem increasingly willing to label false assertions made by politicians that demonstrably aren't true.

By the way, this subject may put you in mind of a supposed quotation popularized by the film The Big Short: "It ain't what you don’t know that gets you into trouble. It's what you know for sure that just ain't so." The movie misattributes it to Mark Twain (whose birthday was yesterday, November 30, by the way), but the line doesn't appear in Twain's published works. Quote Investigator traces a similar line to another 19th-century humorist, Josh Billings.

On the other hand, as Alex Shepard pointed out in The New Republic (or its website, anyway), the book the movie was based on (The Big Short by Michael Lewis) accurately quotes Leo Tolstoy as saying something along similar lines:

The most difficult subjects can be explained to the most slow-witted man if he has not formed any idea of them already; but the simplest thing cannot be made clear to the most intelligent man if he is firmly persuaded that he knows already, without a shadow of a doubt, what is laid before him.

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Timothy Noah's advice to journalists on dealing with Trump's errors

Trevor Noah, host of Comedy Central's The Daily Show, has some advice to journalists on dealing with the flood of false statements from Donald Trump.

(I'm going with "false statements" rather than "lies" because at least some of the time Trump probably believes what he's saying, though other times he is pretty obviously lying.)

Basically, Noah says, Trump argues like a toddler, making stuff up as he goes along, like his entirely made-up claim that millions of illegal votes gave Hillary Clinton her victory in the popular vote (or the "so-called popular vote" as Trump weirdly called to it).


Link: https://youtu.be/9P1IVQJdVvE

Alas, while Noah is right that paying attention to Trump's fantasy world takes away time from reporting on reality, his proposed solution isn't likely to work. He suggests asking Trump questions the way one would a toddler. The problem is that Trump will simply ignore the questions or declare them evidence of media bias or some such.

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Trump transition planning on SNL

You've probably already seen this by now, but in case if you haven't, it's Saturday Night Live's take from the November 19 broadcast on Trump's transition planning since the election.


Link: https://youtu.be/JUWSLlz0Fdo

Trump complained about the show on Twitter, as you'd expect, but news items Monday and Tuesday suggest the writers got several things right, including the decision not to try to jail Hillary Clinton as he'd promised his followers and a growing realization from Republicans that repealing "Obamacare" would hurt a lot of people, including many members of their own party.

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Computer scientists Margaret Hamilton and Grace Hopper awarded Medal of Freedom

President Obama today awards the Medal of Freedom to Margaret Hamilton, not the late actress famous for playing the Wicked Witch of the West but a pioneering computer scientist who programmed computers for the Apollo missions to the Moon and is still alive and in business at the age of 80.

One of Hamilton's most important contributions was in systematically anticipating problems including human error and developing error detection and recover code. Hank Green has a brief explanation of that in this video from June:


Link: https://youtu.be/PPLDZMjgaf8

For more on Hamilton see this article from MIT News and this one about the famous photo showing her standing next to a giant stack of printouts containing the Apollo software. If you want to see the code itself, it's on line here.

The Medal of Freedom will also be awarded posthumously to Grace Hopper, who became a naval officer at the age of 37 during World War 2 and helped develop some of the first high-level computer languages and compilers. I met Admiral Hopper nearly 40 years ago while she was still on active duty and still somewhere have one of the "nanoseconds" she was famous for handing out, a piece of wire one light-nanosecond long. (That's a hair under 30 centimeters, or just short of a foot.) I'm rather surprised she had not already received the Medal of Freedom. She died in 1992, still employed in her post-Navy job at Digital Equipment Corporation.

In her later years Admiral Hopper was best known as a witty and entertaining public speaker. Here's her appearance on the Letterman Show shortly after she retired from active duty at the age of 79 in 1986, and you can see why people enjoyed her talks:


Link: https://youtu.be/1-vcErOPofQ

There's more on Hamilton and Hopper in this article.

Other honorees at today's ceremony include human rights activist Elouise Cobell (deceased), architect Frank Gehry, artist May Lin, athletes Kareem Abdul-Jabbar and Michael Jordan; educator Eduardo Padrón, entertainers Tom Hanks, Ellen DeGeneres, Robert De Niro, Robert Redford, Diana Ross, Cicely Tyson, Bruce Springsteen, and Lorne Michaels; former FCC head Newton Minow, scientist Richard Garwin, American Indian activist Elouise Cobell (deceased); sports announcer Vin Scully, and philanthropists Bill and Melinda Gates. For more see this page on the White House website.

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Your toilet seat might be the only thing in your house more sanitary than your floor

OK, the headline might be a slight overstatement, but not much of one. At least in terms of the number of disease-causing bacteria, floors tend to be cleaner than kitchen counters and toilet seats cleaner than both. Seriously.

Pediatrician and medical professor Aaron Carroll talks about this below after briefly debunking the five-second rule yet again. (That's the nonsensical folk belief that if you drop something on the floor it takes five seconds for it to get contaminated, as if bacteria were too initially startled to jump on it, or something.)

As Carroll says, you can react to this information by obsessively cleaning everything, or you can recognize that germs aren't all that scary a menace. There are reasonable precautions you can take, especially washing your hands with soap and water a lot. (Following food preparation guidelines also makes sense.)


Link: https://youtu.be/XMgBgU8IwfM

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Misunderstanding the Black Lives Matter movement

Things often involve more than their names might imply. Case in point: Black Lives Matter.

A lot of people react to the phrase "Black Lives Matter" without taking time to understand what's behind it. It was prompted by a series of incidents in which government authorities in a number of places in the U.S. seemed to treat black lives as mattering less than others. Members of Black Lives Matter have proposed a number of practical steps to improve matters, such as better police training.

As with anything else, there are legitimate grounds for disagreement. Some cases that have been cited by BLM advocate may not actually reflect racial bias or police misconduct (though plenty of others pretty clearly do). There are other cases involving white victims of police misconduct that would probably be held up as examples of racism were the victim black. (This one, for example.) That is, bad behavior on the part of the police can have other causes than racial prejudice. It's worth noting that a lot of Black Lives Matter ideas (including better police training) would probably help no matter what the underlying cause.

But some objections to BLM simply miss the point. Yes, all lives matter. Yes, the vast majority of black homicide victims are killed by people of the same race. (That's also true of white homicide victims, by the way.) Yes, homicide rates are higher for black people than for white people. Black Lives Matter doesn't say otherwise; it's just addressing something else that's a legitimate topic of concern. Maybe it would have been clearer if BLM had adopted the slogan "Black Lives Matter Too."

Here vlogger Vi Hart summarizes the history of the Black Lives Matter movement. I have quibbles with some of what she says, but in the main I think it's a useful and interesting little video essay.


Link: https://youtu.be/eaEeEbP16Wg

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