Wednesday, January 14, 2015

Stephen Hawking's voice

Stephen Hawking in the 1980s
I learned something interesting today: I am among the last people who ever heard Stephen Hawking's real voice.

On Tuesday, April 23, 1985, Hawking gave a talk titled "Why Time Goes Forward" at Mandel Hall at the University of Chicago. I was a freshman that year, and I was in the audience.

In 1985 (30 years ago!), Hawking was pretty much the figure you see on the cover of "A Brief History of Time," published three years later: wheelchair-bound, bone-thin, as twisted as tree roots. He spoke in a hoarse, squeaky whisper. Essentially unintelligible, except to people in his inner circle, he was accompanied on stage by an English graduate student, bluff and robust, albeit with slightly thinning blond hair, who "translated" him phrase by phrase.

It was like listening to an oracle. Hawking would laboriously emit 30 seconds or so of rasps and squawks. These were in fact sentences, well-crafted and dense with thought, which the grad student would render in plummy Oxbridge tones. There were some jokes mixed in. To my great elation, as the talk progressed and my ear grew attuned, I was able to discern a couple of phrases amid the squawks, confirmed by the ensuing repetition.

What I did not know until now is that Hawking lost his voice just a couple of months later. Via Wired's great article on Hawking's IT and voice synthesizer setup (HT The Browser), I learned that he caught pneumonia in summer 1985 while visiting CERN in Geneva, and had to have an emergency tracheotomy. Since then, according to Wired, his voice has been that of "Perfect Paul," a voice developed for an early text-to-speech synthesizer by an MIT engineer, Dennis Klatt, who used his own voice as a model.

I remember Hawking's Mandel Hall talk fairly well, which is good, because the journal entry I wrote afterward gives maddeningly little detail, (though I did note for posterity that the grad student sported a yellow necktie). Hawking began by showing us a short film of plates falling off a table, then ran the same film in reverse. In real life, shards don't leap off the floor and reassemble themselves into chinaware, but why not? You can't find time-directionality in physics equations as such. They're all time-symmetric.

That led into a discussion of the various "arrows" of time. Hawking mentioned three: the entropic (the direction of increasing disorder), the psychological (which points in the same direction as the entropic, since brain processes are physical processes) and the cosmic (the direction taken by the universe).

When the universe is expanding, the cosmic and entropic arrows point in the same direction. When the universe is contracting, however, entropy is decreasing, so the entropic arrow flips. This raises the unsettling possibility that sentient beings in a contracting universe could believe themselves to be living their lives forward from birth to death, making choices and controlling their fate, when in fact the universe is rolling serenely in the other direction scrolling them backward from death to birth. If that were the case, those sentient beings -- us, for example -- would never know the difference.

Hawking closed by suggesting that the universe could be a "smooth" space-time object, without a tell-tale singularity (i.e., the Big Bang) that you could point to and say, "This is where it started." It wouldn't need a beginning, it would just be.

Heady stuff -- "mind-blowing," says my skimpy journal entry. A lot of it is in "A Brief History of Time." How much of it physicists currently consider tenable, I haven't a clue.

A few years later, I listened to an audiobook narrated by Hawking in his synth-voice, and I remember thinking what an extraordinary evening that night at Mandel Hall had been. I now know I was even luckier than I realized.

Saturday, January 3, 2015

How to lie about flu vaccines in one easy step

I wrote a news article on flu the other day, and a reader emailed me asking, "How many people who get the flu got a flu shot?" I did a couple basic calculations and discovered something interesting (well, interesting to me anyway): The more people get the flu shot, the more easily the resulting statistics can be used deceptively to imply the vaccine doesn't work!

Why? I believe it's known as "conditional probability." Anyway, here are the numbers I ran:

According to the Centers for Disease Control and Prevention, the flu shot cuts people's chances of getting the flu by about 60%. (It depends on your age and health status, the accuracy of the vaccine that year, and so on, but we're talking back-of-the-envelope numbers here.) WebMD says your odds of getting the flu are 5% to 20%. I used 10% as my baseline (i.e., pre-vaccine) risk. For population, I chose 500,000, roughly the number of people in my county.

CASE A: Suppose 50% of the population gets a flu vaccine. (The actual 2013-14 rate was 46.2%.) That means 250,000 people are unvaccinated, while 250,000 get the shot. Of the first half, 10%, or 25,000, will get the flu. Of the others, 25,000 would have gotten the flu, but they have protection that's 60% effective, so only 40%, or 10,000, actually come down with it.  That still gives us 10,000 people complaining that the vaccine didn't do them a lick of good, but our population of 25,000 people who didn't get vaccinated and subsequently got sick is 2 1/2 times larger. Clearly, vaccination is doing its job.

CASE B: Now suppose that 90% of the population, 450,000 people, get a flu vaccine, and only 50,000 don't. We're protecting a lot more people: The vaccine will really show its worth now, right? Let's see.

Among our 50,000 unvaccinated people, 5,000 (10%) will get sick. As for the vaccinated majority, 10% of 450,000 is 45,000, but they have 60% protection, so only 40% get sick. Unfortunately, 45,000 times 0.4 is 18,000. Horrors! Among or population of sick people, the number who got vaccinated vastly exceeds those who didn't. To be precise, the vaccinated group accounts for 78% of the total. Clearly, vaccines are dangerous and make you more likely to get flu!*

CASE C: If the CDC could achieve 99 percent vaccination compliance, then in my hypothetical population of 500,000, there would be 20,300** flu cases, and 19,800 of them - over 97%!! - would be people who got the shot.

When you work it out step by step, it's easy to see what's happening here - a smaller portion of a large number can be (much) bigger than a larger portion of a small number. But if you're innumerate, a writer of clickbait headlines, an anti-vaxxer, or some combination of the three, you write PATIENTS SICK WITH FLU 97% MORE LIKELY TO BE VACCINATED THAN NOT and all hell breaks loose.

The moral: The worse the stats look, the better off we are! 

The follow-up moral: Get a flu shot.

*In case it isn't sufficiently obvious, this "inference" is 100% wrong.

**Note that our total case numbers drop as vaccination spreads: 35,000 to 23,000 to 20,300. Even at 60% effectiveness, vaccination works.




Saturday, December 6, 2014

A trio of Sentences to Ponder

All three encountered this week in articles that are well worth reading in full. (HT for No. 3 to Mike the Mad Biologist.)

From "Sorry New York Times, the state of American marriage is not good": "A married upper class and an unmarried peasantry is exactly what you see when you look at the British Isles in the early 20th century."

● From "Is Uber's rider database a sitting duck for hackers?": “Most people,” Lewis said, “have really bad operational security.”

● From "What schizophrenia can teach us about ourselves": "In Europe, people are generally more comfortable with the ambiguity between psychosis and religion ..."

Saturday, November 22, 2014

A negative argument in favor of human rights

Thomas Jefferson: Smart dude. 
I had a discussion with a colleague this week that touched on the question of human rights. My colleague said that in in his view, the concept necessarily has a religious underpinning: You can't have human rights without presupposing a God who grants them. It's right there in the Declaration of Independence:
We hold these truths to be self-evident; that all men are created equal, that they are endowed by their Creator with certain unalienable Rights; that among these are Life, Liberty and the pursuit of Happiness ...
Far be it from me to cast aspersions on Thomas Jefferson, indisputably one of the greatest intellects of his age, or any age. But we have learned a few things since 1776. We know that the human species wasn't created; it evolved. And while many people believe that at some point, God turned up and inserted souls in us ... I can't see it. We're primates, natural and mortal, down here all by ourselves. Sad but true. Deal with it.

How then can I justify my belief in universal human rights? I do so negatively, by noting how bad the arguments against them are. Here's how it goes:

When I look inside myself, I find I have certain desires and goals, as well as certain aversions. I'd like to keep living, I'd like to have some scope of action to achieve my desires and goals, and I'd like to, you know, actually achieve them. I'd prefer not to suffer pain, despair and death. Let's call this a general preference for "life, liberty and the pursuit of happiness."

Looking at other people, I can rationally conclude they have similar desires, goals and aversions, broadly speaking. I know this because (a) they act that way; (b) biology and psychology tell me they're built basically the same way I am.

Now, it turns out, human life being what it is, that those other people and I will have a better chance of achieving our goals if we cooperate. No man is an island, and all that. We have to form teams. OK, what kind of team should I be willing to join?

Consider the simplest case of a team: a dyad. Two people, A and B, can relate in one of three ways: A outranks B, A and B are equal, or B outranks A.

If I'm A, it's pretty clear which of these arrangements I prefer. Suppose I propose to B the setup "A outranks B." I get to order him around, and dispose of the goodies our team obtains as I see fit. B objects, naturally enough.

What answer can I offer? I basically have two choices. I can either say (a) "This arrangement will work out better for you than the alternatives," or else (b) "My wellbeing counts for more than yours."

The success of (a) depends, ultimately, on whether it's true. Maybe it is! B may survey his desires and goals and decide it's in his interest to use his powers of free action to follow my lead. I believe we call this "the just consent of the governed."

(Communism and fascism, by the way, were failed (and coercive) arguments of type (a). "Follow us and we'll make your life better." Didn't work.)

How about my argument (b)? To put it plainly, it sucks. B has no reason whatsoever to prefer me achieving my goals and desires to him achieving his; quite the opposite. He's he and I'm me. I sure wouldn't accept that argument if he made it! And we're basically the same kind of entity, so if I wouldn't buy it, I can't argue that he should.

But what if he's not the same kind of entity? That, historically, has been the justification for granting human rights to some people but not others. "We're fully human, you aren't." To me, one of the great achievements of naturalism is to show how terrible those arguments are. To a first approximation, everybody's human, so everybody deserves human rights. It's not metaphysics, it's straight-up empiricism.

Pushing that thought a little further, I don't think it's coincidence that the "my wellbeing counts for more than yours" argument tends to come wrapped in a thick layer of self-interested theology. "My God says we are his Chosen People." "This is my Promised Land." "I rule by Divine Right." And so on. I think it's a great step in grounding human rights to realize what terrible justifications those are. "I made up an imaginary friend, and he tells me my narcissism is A-OK." R-i-i-i-g-h-t.

So there's my argument: Human rights exist because I want to have them, and from my naturalistic standpoint, I don't have any coherent justification for awarding them to myself without awarding them to everyone else, too. QED.

One final point. I do think it's the case that the concept of human rights arose out of the Christian tradition. But how could it not? All social thinking in early modern Europe was saturated with Christianity. It was used to justify everything, from the Brotherhood of Man down to slavery, torture and murder. And for a good reason: There wasn't anything else to work with.

Now there is, and we should use it. Contingent history doesn't imply conceptual necessity. We don't have to ground our social systems in medieval theology any more than we have to build planes with canvas wings, just because that's how the Wright brothers got into the air.


Saturday, October 18, 2014

Ramen and cholesterol: I am a world authority!

Mind the palm oil.
A little over a year ago, I wrote a blog post titled "Ramen, my cholesterol and the history of the world," explaining how I'd been blithely treating instant ramen noodles as a health food, when in fact they're chock-full of palm oil, which is basically the stuff you put in your veins when your goal is to help your local cardiac surgeons pay off their student loans early. 

The post got a fair number of hits, which is always nice. Then, a couple of months ago, I noticed something weird: It had become the No. 1 result for the Google search on the words "ramen" and "cholesterol." Try it! As of this writing, it was still the case. 

That should tell you something about the reliability of the Internet. I'm not a nutritionist, and make no pretense of being one. Nor have I delved deeply into the ramen-cholesterol link: I read one NPR article, photographed the back of a package, and wrote a single post. But as far as Google's search algorithm is concerned, I'm your go-to guy.

So, on Tuesday, I get this:
Hi,
I hope all is well with you.  Healthline just published an infographic detailing the effects of high cholesterol on the body.  This is an interactive chart allowing the reader to pick the side effect they want to learn more about. You can see the overview of the report here
Our users have found our guide very useful and I thought it would be a great resource for your page: "Ramen, my cholesterol levels and the history of the world."
I would appreciate it if you could review our request and consider adding this visual representation of the effects of high cholesterol to your site or sharing it on your social media feeds.
Please let me know if you have any questions.
All the best,
Maggie Danhakl • Assistant Marketing Manager

Become a scare-quote "expert," and you get solicitations from real ones! I went and checked out Healthline's site. Their cholesterol graphic is indeed attractive (click it to visit the original):

On their site, when you point to the various organs, you get a popup with more information. Also, their information, unlike mine, has been medically reviewed by an actual doctor, George Krucik, MD, MBA.

So by all means, check out Healthline. Happy to oblige, Maggie! Also, go easy on the instant ramen.