Re: Trivers' Reciprocal Altruism

From: Stevan Harnad (
Date: Mon Nov 17 1997 - 17:55:40 GMT

> From: Tommy <>
> After
> rereading the paper it doesn't seem so difficult to see that
> it's use on humans is all that wrong (just on a different
> level).

I'm not sure (with these double negatives) whether you meant it's
right or it's wrong!

> If a fish cheats by eating it's cleaner it will have to find
> a new one and risk contact with cheat 'mimic' cleaner fish.
> The same is true of humans- unreciprocating behaviour may
> cause the breaking down of a relationship and the search for
> other friends.

It's not quite the same: A fish with a gene that lets him eat the
cleaners will not get cleaners, will get parasites and die, thereby NOT
passing on his unfortunate tendency towards cleaners.

If we abandon a friend because we find he has cheated, this does not
affect our chance of survival and reproduction. But having been
uninterested in monitoring whether friends pay back our favours in the
EEA may have led to selection against that unfortunate uninterested

Be very careful not to mix up proximal and distal causes. Trivers would
say that the tendency toward reciprocal altruism was shaped distally,
in the EEA, and was based on survival differences between selfish genes
(those of reciprocators and cheaters). A friend who fails to reciprocate
today is influencing my proximal tendency to monitor reciprocity; but my
survival/reproduction has nothing to do with it today, whereas the
fish's does, because he's still in his EEA.

> Thus they risk exposure to forms of cheating.
> Therefore natural selection favours altruism as long as there
> is an efficient regulatory system, and this is probably where
> the criticisms lie in the jump from non-human to human
> altruism.
> Cheating is very cut and dry in the examples of non-human
> species -The big fish cheats by eating the cleaner, the
> cleaner fish are invaded by mimics who hope that they don't
> get caught.
> Where in humans the variables are much greater in our form of
> social interaction and therefore our regulatory system must
> account for the varying levels altruism and it's effects in
> different situations. So the cost-benefit ratio would be more
> complex but the result 'could' have been worked out through
> unconscious processes which form a conscious emotion which is
> behaved upon.

Kid-sib understood the first two paragraphs above, but not the third
one: What is your point here? That the reciprocity is tracked
unconsciously rather than consciously?

> The same idea of unconscious processes was used in an example
> from Sperm Wars, I think it went something like this; If a
> woman is unfaithful it prompts a conscious feeling of guilt
> towards her partner increasing the chances of her having sex
> with him. However, the guilt feeling may be a byproduct of
> the subconscious desire to start a sperm war (so insemination
> is by the strongest swimmers).

Okay, then, yes, these unconscious mechanisms are similar in monitoring
reciprocity as well as in inducing sperm wars. I should think the
reciprocity is a more conscious mechanism: We are aware when someone
we've helped fails to help us. I'm not sure, though, that our
resentment toward people who don't pay back favours needs to be accounted
for in terms of EEA mechanisms. It's so easy to explain on the basis of
rationality alone; then we would owe our rationality to the EEA, but not
our attitude towards cheaters.

Everyone should be reflecting on when the EEA explanations are more
plausible and where less.

> The unconscious message in reciprocal altruism may be to
> protect against cheats, so when someone is unreciprocating
> there is a conscious feeling of aggression which prompts
> behaviours such as; -to stop the friendship -make other feel
> guilty so they act altruistically later -punish other etc.

Kid-sib had a bit of trouble with that sentence too, but do we really
need an EEA explanation for our resentment toward people who take favours
but do not give them? I mean, why invoke the EEA there and not in
the case of cheating in a poker game or soccer: They make as pretty
angry too, but surely the anger does not go back to some old games played
in the EEA (or does it?).

> Of course this is a pretty basic scenario but it seems
> relevant enough to be considered as a possible regulatory
> system for human altruism. A more complicated example would
> just involve a more complex cost-benefit ratio analysis (to
> arrive at an outcome that is situation specific).
> Either way this type of talk of unconscious processes/emotion
> based behaviour is all speculation of what the cause might be.

Kid-sib had problems understanding this too (except the last sentence).

> Part of the argument (in the tutorial) against the use of
> Trivers' model on human alt. beh. was the scenario of the man
> who formed a 'human bridge' on a sinking ship for people
> other than his kin.

Why is that against Trivers? He explains altruism as not only an effect
of inclusive fitness (kindred genes) but but also as an effect of
helping and monitoring for reciprocation.

If we tend to help nonkin assuming they will pay us back, then this
heroism would just be of the same sort: they would do it for me too.
I'm sure that if one of the people he had saved later failed to help
the hero, he would feel resentful.

> It doesn't seem that this question need worry the Trivers
> paper, it seems better to put this to the selfish gene. In
> terms of the selfish gene he should have helped his kin and
> then got out himself,

But the Trivers paper is NOT about helping kin, but about helping

> however we go against our genetically
> predetermined behaviour all the time ( Dawkins noted that
> cultural practices can override biological predispositions and
> tried to explain it in terms of memes).

This deserves more discussion.

> The biggest must be the decision not to have children. We are
> genetically designed to reproduce and live in a social context that to
> some extent promotes it. It can't be a biological trait and if it were
> it would have been selected out by now. It couldn't have existed in the
> EEA as there is no benefit to the evolution of any species that behaved
> like that. So in choosing not to reproduce (in gene terminology) we
> may as well be dead men/women walking
> I know about helping our genes
> succeed through helping kin. What I think I'm babbling on about is
> that to some extent the integration of human emotion and the ability to
> consciously reflect upon them allows us to break away from the
> biological based origins of behaviour.

Chances are that our CONSCIOUS feelings and decisions about
reproduction have little to do with the reproductive strategies
that worked in the EEA: If you want to know about the effects
of THOSE distal factors you need to talk about feelings like love,
lust, jealousy and perhaps guilt and kindness. THOSE are the emotions
through which our EEA is expressing itself in our day. Our conscious
reproductive strategies have little to do with that, especially since
knowledge of the link between mating and reproducing came well after the
EEA (and had still not reached Stone Age tribes in Papua in our own

> For example; It may have been Mr. human bridge's desire to
> help his genes (kin selection) that got him down there in the
> first place and the underlying emotional dispositions that
> kept him there. e.g.-To gain gratitude -To avoid the guilt of
> not helping others especially if it meant causing their
> deaths.

Kid-sib doesn't understand this.
