Okay, so we have our chimpanzee
banging away at typewriters. Each
keystroke is assumed to be random (this is a thought problem, not a hiring
problem). Let’s limit the keys to the
twenty six letters of the alphabet so I don’t have to count the keys on my laptop. How long does it take our pan troglodytes to
produce Shakespeare’s Richard the Third?
Well, our hairy scribe will
produce one “n” about every twenty-six strokes.
Multiply 26 by 26 and that is how many strokes will be needed to produce
the first two letters “no”. Assuming
that Bonzo types 260 letters a minute, how long will it take him to turn out Now is the Winter of Our Discontent Made
Glorious Summer by this Son of York?
I once actually calculated this
out and quickly determined that it would take more time than the kosmos has
existed for our chimp or indeed a whole army of chimps to get even halfway
through that first line.
I like to use this popular
thought problem to test my philosophy students.
Could chimpanzees produce a Shakespeare play by random typing? The answer is that not only could they do so
but they would inevitably do so, given enough resources including time. The problem is that the requirements are so
vast as to be, for all practical purposes, impossible. She who agrees with what I have just said is
capable of thinking logically. He who
refuses to acknowledge even the contingent possibility is not.
One might say that Darwin
explained how it was not only possible but actual that that random typing
produced chimpanzees. What you need is
some means of saving the good letters.
If every good letter survives and every bad letter perishes, then every
twenty six strokes will get you one letter closer to My Kingdom for a Horse!
Darwin can explain how you get
from the simplest replicating organisms to certified public accountants because
replicating organisms, by definition, have a means of saving and compiling the
good letters in the DNA (or RNA) script.
But how do you get from inorganic chemistry to those UR organisms?
Physicist Jeremy England has an
intriguing guess. His work is discussed
in “How
do you say “life” in Physics” by Alison Eck in Nautilus. England addresses
the problem that life presents to physicists.
To the physicist steeped in statistical mechanics, life can,
in this sense, appear miraculous. The second law of thermodynamics demands that
for a closed system—like a gas in a box, or the universe as a whole—disorder
must increase over time. Snow melts into a puddle, but a puddle does not (on
its own) spontaneously take the shape of a snowflake. Were you to see a puddle
do this, you’d assume you were watching a movie in reverse, as if time were
moving backward. The second law imposes an irreversibility on the behavior of
large groups of particles, allowing us to play with words like “past,”
“present,” and “future.”
The arrow of time points in the direction of disorder. The
arrow of life, however, points the opposite way. From a simple, dull seed grows
an intricately structured flower, and from the lifeless Earth, forests and
jungles. How is it that the rules governing those atoms we call “life” could be
so drastically different from those that govern the rest of the atoms in the
universe?
England’s guess is that the
solution turns on irreversible shifts in states of atoms. Here is my version, which mixes the metaphors
in the Nautilus articles. Someone
jumping a fence with a pogo can jump back, given that she has enough energy to
do so. That’s a reversible change in
state. Someone being shot out of a canon
cannot return. His flight is
irreversible.
How does this work at the atomic
level?
A group of atoms could take a burst of external energy and use
it to transform itself into a new configuration—jumping the fence, so to speak.
If the atoms dissipate the energy while they transform, the change could be
irreversible. They could always use the next burst of energy that comes along
to transition back, and often they will. But sometimes they won’t. Sometimes
they’ll use that next burst to transition into yet another new state,
dissipating their energy once again, transforming themselves step by step. In
this way, dissipation doesn’t ensure irreversibility, but irreversibility
requires dissipation.
Now, if I understand the
argument, a shift in a configuration of atoms that dissipates the energy
required to effect it is a means of saving information. If the configuration acquires more energy and
then jumps to yet another new configuration, then information is in effect
compiled. The third configuration has a
history. To really understand what it
is, you would have to know the steps that led up to it. To the extent that that is true, the history
involves the compiling of information. The
gaggle of atoms is saving the good letters.
This is a very long way from
explaining how genuine organisms emerge out of the inorganic soup. It doesn’t give us any idea of the chimpanzee
typing odds. It does give us an idea of
how the simplest mechanics might have produced a selection pressure that tilted
inorganic processes towards the emergence of life.
The origin of life is one of the
major mysteries. The fact that life did
emerge on planet Earth tells us that inorganic nature contained within it the
seeds of life. I like that idea. England may be onto an important clue as to
where those seeds lay and how they germinated.
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