Bryan Caplan  

How Long Would Peter Pan Live?

PRINT
Did Armageddon Happen?... Mencius Moldbug, Sighted but U...
In 2005, American kids aged 5-14 had a death rate of 16.3 per 100,000.  Here's one way to think about how incredibly low that is:

Suppose a kid could keep that childhood mortality rate forever.  What would be his expected lifespan? 

Answer: 6,135 years!  His median would be a little lower - a mere 4,252 years.

Somehow this makes me more optimistic about the prospects for life extension.  To extend our lifespans to thousands of years, scientists don't have to succeed where billions of years of evolution failed.  They just need to figure out how to lock in the safety that the typical human already enjoys for one of his decades.


Comments and Sharing





COMMENTS (12 to date)
Sulla writes:

How do you calculate that ? o0

Matt writes:

This reminds me of the Heinlein novel Time Enough For Love where everyone is immortal but usually dies in an accident after several thousand years or so.

Bryan Caplan writes:

Take the reciprocal of the probability of death to get the life expectancy. To get the median, you've got to solve for x in the equation (1-p)^x=.5, where p is the mortality rate. Just take logs of both sides.

noahpoah writes:

Some argue that death is an evolutionary adaptation (there's a chapter on it in Nick Lane's very nice Life Ascending). If so, then the only way to 'lock in' the safety of youth would be to 'succeed where evolution has failed', so to speak.

blighter writes:

"scientists don't have to succeed where billions of years of evolution failed"

You seem to be assuming that evolution has been tending towards extremely long life for any given individual but I don't think there's any reason to suppose that would be evolutionarily advantageous. In point of fact, if it were attained or came close to being attained I would imagine it would act as a significant brake on evolution.

Far more likely is that evolution has been trying for billions of years to evolve beings who don't die before they reproduce at least once but after that are better off gone, from evolution's standpoint.

Judging the evidence, I'd say evolution has suceeded admirably and science will have a tough row to hoe in trying to alter reality against a process that best facilitates (and is thus reinforced by) evolution.

Richard A. writes:

"To get the median, you've got to solve for x in the equation (1-p)^x=.5, where p is the mortality rate. Just take logs of both sides."

(1-p)^x=0.5
log[(1-p)^x]=log(0.5)
xlog(1-p)=log(0.5)

x=log(0.5)/log(1-p), p=16.3/100,000=0.000163
x=4252 years

Of coarse for a quick calculation you can always use the rule of 70.

p=0.0163%

x=70/0.0163%
x=4,294 years (approximate)


Jim Hobelman writes:

Strictly speaking the life expectancy is the
reciprocal of the force of mortality.

Steve writes:

All scientists have to do is stop the body from aging?

CAKE

Brandon Berg writes:

Bryan:
Peter Pan gets into fights with pirates and crocodiles and flies around at dangerously high altitudes using only happy thoughts and fairy dust--a substance of dubious provenance and reliability. I'll give you two-to-one odds that he doesn't make it past the six-week mark.

Mark Bahner writes:

"Peter Pan...flies around at dangerously high altitudes using only happy thoughts and fairy dust--a substance of dubious provenance and reliability."

All the rocket men swear by it.

Bill writes:

All scientists have to do to extend human life span thousands or years is prevent death from old age and prevent the break down of the body due to age and long term abuse (Smoking, lack of exercise, extreme obesity). No problem. :)

Patri Friedman writes:

The key reason to be optimistic about aging is David Gobel's "Actuarial Escape Velocity" argument. Basically, if we can rejuvenate people by X years, that extends their lives by more than X years, because they get X years of life, plus X years of rejuvenation research to bring new rejuv treatments.

It turns out that it only takes a modest rate of increase in rejuv technology to get immortality. Right now we gain 0.2years of lifespan per year. As that approaches 1 year/year, lifespans get really long, and at 1yr/yr, old age is a thing of the past:

http://www.singularity2050.com/2008/03/actuarial-escap.html

Comments for this entry have been closed
Return to top