There are two players in this game. During each move, they have the option of cooperating or defecting. They are not bound by their previous choices. If they both cooperate, they are both rewarded. If one defects, the other gets nothing while the defector gets a greater reward than when both cooperate. But if they both defect, both get a very small reward. The players are not permitted to communicate, except by announcing their choices. They must operate on blind trust (or mistrust).
What is the best strategy to use in this game? The way the reward system is set up, BOTH players get the most if they cooperate throughout the game. But, there's always the temptation to defect in order to receive the higher reward.
Axelrod ran a computerized Prisoner's Dilemma tournament, inviting programmers to submit software that employed various strategies of play. These programs embodied a variety of rules for cooperating or defecting, based on the other player's previous moves. The most effective program in point totals after round-robin play was TIT FOR TAT. This program always cooperated on the first move, and thereafter cooperated or defected according to what the other player did on the previous move. This simple strategy allowed TIT FOR TAT to get a wide variety of programs to cooperate with it.
By studying the results of the tournament, Axelrod discovered that cooperative relationships become stable when all parties see the relationship lasting for a significant amount of time, when cooperative behavior brings rewards unattainable otherwise and when other parties are able and willing to retaliate swiftly for any defection.
Cooperative relationships spring up under the most adverse situations. During World War I, the men in the trenches would not fire on one another during lulls between large battles unless directly ordered to do so by a superior officer. Generals tried their best to break up the cooperative relationship along the front, but with little success.
Many animal species establish territories. This apparently conflict-ridden practice actually engenders cooperation because it allows individuals to have continuing relationships with their neighbors. The front in World War I often remained stationary for months, allowing soldiers to get to know one another across the barbed wire and giving them time to trust each other.
In humans, the tendency toward cooperation is magnified by the human traits of self-reflection and ability to plan ahead. Watch people in any large convention hall. Notice how close they sit together without fighting. This could never happen with a hall full of uncaged dogs.
The huge array of human institutions that require people to cooperate sight unseen testifies to the power of this deeply engrained behavioral system. In a wide range of situations, cooperation is the most effective strategy for all sides. The world is not normally a zero-sum gam and one is not required to overcome others to win. It shouldn't surprise us to find the cooperative strategy as pervasive as it is, especially considering the powerful universal forces that undergird it and shape it.
A mind can be described as a cooperative venture, a society of many small processes combining into larger, more powerful processes. One of the most powerful of these is the conscious self.
Douglas Hofstadter described these processes with a poetic analogy in "Godel, Escher, Bach": "If it were possible to schematize this whole image, there would be a gigantic forest of symbols linked to each other by tangly lines like vines in a tropical jungle--this would be the top level, the Tangled Hierarchy where thoughts really flow back and forth. This is the elusive level of MIND."
Hofstadter's idea of Tangled Hierarchy fits in with what is now known about the operation of the brain. Loops within loops of activated neurons, signals, and symbols of thought create a conscious mind which, in turn, reaches down and alters its own lower-level processes. Mind grows out of pattern of patterns and establishes itself as the great pattern.
Marvin Minsky in "The Society of Mind" postulates that this layered intelligence comes into being during our long childhood. We learn about the world by inferring the existence of simple rules and conducting experiments to see if they really work. Children do this unconsciously by bouncing balls, building block towers and knocking them down, taking things off other things, hiding things and finding them--in other words, by playing.
We build a hierarchy of knowledge about the world in these earliest of experiments. Groups of rules generate metarules, which generate metametarules, and so on. Over years of hard practice, we imbue our world and ourselves with meaning.
Minsky explodes a common misconception about common sense: "Common sense is not a simple thing. Instead, it is an immense society of hard-earned practical ideas--of multitudes of life-earned rules and exceptions, dispositions and tendencies, balances and checks."
And now, we arrive at the ancient mystery. How can these neurons, signals and symbols build something as powerfully real as the sense of self? Hofstadter defined the self as the reflective symbol in the mind. Free will arises as the self symbol interacts with and changes the other higher level symbols of the mind deliberately. You have a thought. It leads to another thought. You decide you don't like that thought, so you think of something else instead. You decide what to change. You act freely. And you realize that your ARE acting freely.
Hofstadter explains more fully: "A very important side effect of the self-subsystem is that it can play the role of 'soul' in the following sense: In communicating constantly with the rest of the subsystem and symbols in the brain, it keeps track of what symbols are active, and in what way. This means that it has to have symbols for mental activity--in other words, symbols for symbols, and symbols for the actions of symbols."
When we think we are most separate from the universe, it turns out we're that much more closely linked with the processes that made us. We are as much a part of the natural order as leaves spread out in the sunlgiht, atoms forming in the crucible of a supernova, and a child at play.