[extropy-chat] Love of paradox

Hal Finney hal at finney.org
Mon Mar 20 04:49:08 UTC 2006

One of the things that I enjoy most is learning about paradoxical and
surprising results.  Of course, life is full of surprises, not all of
them good.  But even a bad surprise often has a silver lining.

My favorite types of surprises are scientific facts which run contrary
to the conventional wisdom.  One of these is what we have been discussing
recently, the apparent lack of impact of traditional medical treatments on
the steady improvement in life span over the last 100-250 years.  I was
as surprised as anyone when Robin first mentioned it (several years ago,
I think).  Like many of us, I didn't see how it could possibly be true.
The preeminent role of medical treatment in extending lifespan seemed
as rock solid as any of my beliefs.

But once Robin mentioned it a few times, and I realized he was serious,
I found the idea highly appealing.  It's an amazing, unexpected and
paradoxical result that runs completely counter to common sense.  To me
that makes it fascinating and exciting.

Robin is a good source for these kinds of surprises.  Another one is
his work on the astonishing claim that it is impossible for rational
people to agree to disagree about something.  Again, nothing could seem
more obvious than that intelligent, rational people can disagree about
a matter in a stable, consistent and fully respectful manner.  Yet I now
know that a wide range of results in economics and game theory show that
this is not true (modulo certain exceptions, which Robin and others are
gradually pushing back).  It came as a total and delightful shock and
surprise to me and has had a major impact on my thinking.

Yet another paradoxical result that we discuss occasionally is the Flynn
effect, which notes that IQ tests have had to be renormalized every
generation because people constantly do better on them.  The result is
that IQ has risen effectively about 3 points per decade for at least
100 years.  This again flies in the face of the conventional wisdom
which is either that intelligence is constant since prehistory, or more
cyncally, that modern day innovations like television are making people
less intelligent.

I got into my own field of cryptography largely because it is founded
on paradox.  I well remember the astonishment I felt when I first learned
about public-key cryptography from Martin Gardner's Scientific American
column back in the 1970s.  Two people can exchange messages such that
each message is heard by an eavesdropper, yet after a few exchanges and
some simple mathematics, they can send a secret message from one to the
other and there is no way the eavesdropper can read it.  When you first
hear it, it sounds completely impossible and crazy.  If the eavesdropper
can hear everything, it would seem there is no way the two people can
transfer any kind of secret.  Yet the RSA algorithm and others have
proven highly practical and effective.

I didn't get into crypto right away, but I was always fascinated by it,
and then when the PGP software came out around 1991, I downloaded it and
started playing with it.  I ended up doing some patches and communicating
with the inventor, Phil Zimmermann, and soon we were working together
on the next version of PGP.  Eventually Phil started a company to
commercialize the software and when he gave me an opportunity to work
there (out of my home in Santa Barbara, no less) I jumped at the chance.
I've worked on PGP ever since, over ten years now, and I still find PK
crypto as fascinating as ever.  The fundamental paradox at the heart of
the field is what continues to hold my interest.


More information about the extropy-chat mailing list