184
9 Networked Minds
9.9 Making Mistakes Is Important!
How does this preference to show regard for others evolve? First, it is important
to recognize that a low, but finite level of friendliness is generated due to the
random mutations of the friendliness values of offspring. Second, this slight preference to show regard for others creates conditionally cooperative behavior. That
is, if just enough neighbors would cooperate, a “conditional cooperator” will be
cooperative as well.
Third, unconditionally cooperative individuals with a high level of friendliness are
born very rarely, and only by chance. These rare “idealists” will usually be exploited.
They receive poor payoffs, and have no offspring. However, idealists may catalyze
cooperative behavior if he/she is born by chance into a neighborhood with a sufficient
number of conditionally (or unconditionally) cooperative individuals.
17
Fourth, in the cooperative neighborhood resulting from such cooperation cascades,
high levels of friendliness are passed on to many offspring and thus, the preference to
show regard for others rapidly spreads. This happens because friendliness becomes
more profitable than in the initial phase of the evolutionary process, when friendly
people are lonely idealists who are exploited by others. Many generations later,
however, those who cooperate earn a higher payoff on average than those who act
selfishly. This makes sense for the following reason: if everyone in the neighborhood is friendly, everyone has a better life. Therefore, while “homo economicus”
initially earns more, “homo socialis” eventually outperforms “homo economicus”
(see Fig. 9.3). As a consequence, the levels of friendliness increase over sufficiently
many generations, but they are broadly distributed (see Fig. 9.4). This explains the
large variety of individual preferences which is actually observed: in our society, we
encounter everything from selfishness to altruism.
Note that in the situation studied above, where everyone starts out as a noncooperative “homo economicus”, no single individual can establish profitable cooperation, not even by optimizing decisions over an infinitely long period of time.
Therefore, “homo socialis” can only evolve thanks to the occurrence of random
“mistakes” (in this case, the birth of unconditionally cooperative “idealists” who are
exploited by everyone). If such “errors” happen by coincidence in the neighborhood
of other idealists or conditionally cooperative people (i.e. sufficiently friendly individuals), this can trigger a domino effect that causes an “upward spiral” towards
more cooperation and eventually changes the society to the better. Then, cooperation yields higher payoffs than selfishness and “loving your neighbor as yourself”
becomes rewarding.
In conclusion, the cooperativeness of “homo socialis” does not result from optimization, but from evolution. While being an idealist is a painful mistake in the
17 One might think that this is what happened, for example, in the case of Jesus Christ. He preached to
“love your neighbor as yourself”, i.e. other-regarding behavior weighting the preferences of others
with a weight of 0.5. His idealistic behavior was painful for himself. He ended on the cross like a
criminal and without any offspring. But his behavior caused other-regarding behavior to spread in
a cascade-like way, establishing a world religion.
9 Networked Minds
9.9 Making Mistakes Is Important!
How does this preference to show regard for others evolve? First, it is important
to recognize that a low, but finite level of friendliness is generated due to the
random mutations of the friendliness values of offspring. Second, this slight preference to show regard for others creates conditionally cooperative behavior. That
is, if just enough neighbors would cooperate, a “conditional cooperator” will be
cooperative as well.
Third, unconditionally cooperative individuals with a high level of friendliness are
born very rarely, and only by chance. These rare “idealists” will usually be exploited.
They receive poor payoffs, and have no offspring. However, idealists may catalyze
cooperative behavior if he/she is born by chance into a neighborhood with a sufficient
number of conditionally (or unconditionally) cooperative individuals.
17
Fourth, in the cooperative neighborhood resulting from such cooperation cascades,
high levels of friendliness are passed on to many offspring and thus, the preference to
show regard for others rapidly spreads. This happens because friendliness becomes
more profitable than in the initial phase of the evolutionary process, when friendly
people are lonely idealists who are exploited by others. Many generations later,
however, those who cooperate earn a higher payoff on average than those who act
selfishly. This makes sense for the following reason: if everyone in the neighborhood is friendly, everyone has a better life. Therefore, while “homo economicus”
initially earns more, “homo socialis” eventually outperforms “homo economicus”
(see Fig. 9.3). As a consequence, the levels of friendliness increase over sufficiently
many generations, but they are broadly distributed (see Fig. 9.4). This explains the
large variety of individual preferences which is actually observed: in our society, we
encounter everything from selfishness to altruism.
Note that in the situation studied above, where everyone starts out as a noncooperative “homo economicus”, no single individual can establish profitable cooperation, not even by optimizing decisions over an infinitely long period of time.
Therefore, “homo socialis” can only evolve thanks to the occurrence of random
“mistakes” (in this case, the birth of unconditionally cooperative “idealists” who are
exploited by everyone). If such “errors” happen by coincidence in the neighborhood
of other idealists or conditionally cooperative people (i.e. sufficiently friendly individuals), this can trigger a domino effect that causes an “upward spiral” towards
more cooperation and eventually changes the society to the better. Then, cooperation yields higher payoffs than selfishness and “loving your neighbor as yourself”
becomes rewarding.
In conclusion, the cooperativeness of “homo socialis” does not result from optimization, but from evolution. While being an idealist is a painful mistake in the
17 One might think that this is what happened, for example, in the case of Jesus Christ. He preached to
“love your neighbor as yourself”, i.e. other-regarding behavior weighting the preferences of others
with a weight of 0.5. His idealistic behavior was painful for himself. He ended on the cross like a
criminal and without any offspring. But his behavior caused other-regarding behavior to spread in
a cascade-like way, establishing a world religion.