Non-Zero: The Logic of Human Destiny by Robert Wright, Little, Brown,
拢22.50, ISBN 0316644854
ARE intelligent creatures inevitable if evolution is left to do its business
long enough? Is increasing complexity an essential feature of biological and
social evolution?
Yes, says Robert Wright in his new book Non-Zero: the Logic of Human
Destiny. This may seem banal: after all, until life has become complex, the
arrow of evolution can鈥檛 go the other way. But self-replicating chemicals need
not have evolved into genes inside cells. Individual cells need not have
combined to form multicellular organisms. And social animals need not have
formed groupings with other individuals. But they all did. Why? Even now, 3.8
billion years later, the trajectory towards increasing complexity is
accelerating, although for humans most changes increase social rather than
biological complexity.
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Wright focuses on the tendency of biological systems to play what are known
as 鈥渘on-zero sum鈥� games. Zero-sum games have winners and losers: one player鈥檚
gain is another鈥檚 loss. In non-zero sum games, both players can win. If two
people can catch a far bigger fish than either could alone, for example, both
profit from the interaction.
At a biological level, a gene that makes a toxin might cooperate with a gene
that makes an enzyme. Together, they may allow an organism to kill and digest
prey; alone, neither gene may prosper.
Wright鈥檚 view is that substantial benefits derive from actors in biological
systems playing non-zero sum games. This has meant that cooperators have
outcompeted the non-cooperators throughout history. And cooperation, Wright
asserts, begets more cooperation, with the upshot that increasingly complex
organisms and, latterly, technological societies emerge.
Wright鈥檚 views are certain to annoy one sect of evolutionary biology鈥檚 broad,
if quarrelsome, church鈥攖hose who believe, largely following Stephen Jay
Gould, that the history of biological evolution is the result of a series of
highly improbable events, without any manifest direction. The evolution of
humans, in this view, was fortuitous rather than inevitable. But even Gould now
grants that there has been a shift towards greater complexity, even if to a
reasonable first approximation all living things on Earth are bacteria-that is,
if one simply counts heads.
Most biologists would agree with Wright that cooperation鈥攁mong genes,
cells, groups and so on鈥攈as been a fundamental force in evolution, even if
the cooperation ultimately serves individual ends. Most would probably even
agree that a tendency towards this sort of non-zero sum cooperation is
inevitable in Darwinian systems, that is, in systems in which natural selection
preserves the fittest actors.
Disagreement may arise in other quarters. Is it the tendency to cooperate or
the flight from danger鈥攖he carrot or the stick鈥攖hat drives the
evolution of biological complexity? Is cooperation the principal route to
complexity or just one of several, including utter domination of adversaries?
Are highly intelligent animals such as humans really inevitable?
The first point is probably mostly semantic. Without the threats of
predators, parasites or cheats, cooperation might not take off so readily. But
it is difficult to imagine Darwinian systems that lack these features.
Whether cooperation is the main route towards greater complexity is less
clear. It is very probably a common route, possibly even the most frequent, but
the role of sheer domination should not be underestimated鈥攏ature was
Hobbesian long before Hobbes asserted that might ruled.
For example, the powerhouse of eukaryotic cells鈥攖he complex cells that
all animals are made of鈥攊s an organelle called the mitochondrion.
Following Lynn Margulis, most biologists now think mitochondria were once
free-living organisms that took up residence in eukaryotic cells. This would
appear to be a classic non-zero sum relationship, because the cell gets its
energy from the mitochondrion while the mitochondrion gains the protection of
the cell.
Wright dismisses the notion that the ancestors of eukaryotic cells enslaved
mitochondria and pilfered many of their functions, leaving a genetically hobbled
organelle that posed fewer risks to the cell鈥攖he rule of might. He
counters that, like domesticated pigs, there are lots of mitochondria that owe
their existence to their 鈥渆nslavement鈥�. But this misses the key Darwinian
currency: it is not how many mitochondria there are in eukaryotic cells that
matters, but how many there might be had they got their way.
On the final question, Wright is emphatic that creatures intelligent enough
to reflect on their own predicament are practically inevitable products of
Darwinian systems. If not us, then some other species with our predilections and
accomplishments would have emerged.
Here Wright courageously wades into a debate that we simply do not know the
answers to, as we are the only known instantiation of this existential creature.
But he wades in armed with a better set of arguments than most. Cooperation
among potentially competing entities has been an opportunistic and creative
force in evolution, and this should intrigue us. If Wright is correct, the
potential of cooperation is and has been so great that it has harnessed the
natural tendency of biological and social systems to turn on themselves in acts
of zero-sum selfish behaviour.
Non-Zero is by turns evangelical and soberly academic. At all points
clearly written and well researched, it gets better and better as it goes on,
and finds Wright speculating near the end about the origins and role of human
consciousness. Anyone with an interest in cultures, warfare, innovation,
cheating, thinking and, yes, cooperation will find this book enjoyable and
thought provoking. If money鈥檚 tight, club together with someone else to buy it:
you will both benefit.
Mark Pagel is in The School of Animal and Microbial Sciences, University of
Reading and editor-in-chief of the forthcomingEncyclopedia of Evolution
from Oxford University Press