Transcript So Cleverly Kind

So Cleverly Kind
Epigenetic rules vs. genetically
endowed potential
Human Nature
• Freud’s dilemma:
– As we become more ‘civilized’ we must
‘renounce more and more of our innate
selves.
– The price of civilization is individual
unhappiness.
• But this is familiar ground: a vision of
ourselves that divides us up between an
animal heritage (violent, impulsive) and a
civilized, restraining overlay.
Evidence?
• Is there any reason to suppose this is really how
things are with us?
• Are our ‘good’ inclinations really artificial,
imposed, unnatural to us,
• Are our bad inclinations really natural, rooted in
our evolutionary past, only to be ‘overcome’ by
some recent, artificial civilizing influence?
• Gould thinks not, and blames this notion on
dualism, theology (not to mention
Manicheanism).
Manicheanism
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•
The most striking principle of Manichaean theology is its dualism. Mani
postulated two natures that existed from the beginning: light and darkness.
The realm of light lived in peace, while the realm of darkness was in
constant conflict with itself. The universe is the temporary result of an attack
from the realm of darkness on the realm of light, and was created by the
Living Spirit, an emanation of the light realm, out of the mixture of light and
darkness.
A key belief in Manichaeism is that there is no omnipotent good power. This
claim addresses a theoretical part of the problem of evil by denying the
infinite perfection of God and postulating the two equal and opposite powers
mentioned previously. The human person is seen as a battleground for
these powers: the good part is the soul (which is composed of light) and the
bad part is the body (composed of dark earth). The soul defines the person
and is incorruptible, but it is under the domination of a foreign power, which
addressed the practical part of The Problem of Evil. Humans are said to be
able to be saved from this power (matter) if they come to know who they are
and identify themselves with their soul.
Influences of Mani
• Christian theology is officially not Manichean.
• In fact, it’s a standard heresy.
• But Christianity has been strongly influenced by
Manichean ideas.
• After all, they did officially brand it a heresy.
• And one can’t help suspecting that some of the early
issues about sexuality that troubled Christian theologians
(is it better to be chaste? What happens to the religious
community if everyone is expected to be chaste?) derive
from the identification of the ‘dark’ with matter (and the
light with ‘spirit’). Purity issues are unavoidable here…
Altruism
• Why is this such a focus here?
• One-shot PD is not solvable without altruism.
• Altruistic behaviour is often selected for very
special praise as ethically ‘impressive’.
• Evolution vs. Altruism: Some, who have a limited
view of what natural selection is about, imagine
that evolution by NS simply cannot make sense
of altruism.
But we know better
• Gould tells us a story about Hamilton’s work on
kin-selection (and Haldane’s anticipation of the
idea).
• So altruistic behaviour can easily evolve in a
context where the recipients of the aid are
related to the givers.
• This is particularly obvious in the widespread
phenomenon of parental aid to their offspring.
• But it’s most striking biological success is in its
applications to the eusocial insects.
Hymenoptera
• These are the ants, bees and wasps.
• There is a peculiar fact about the genetics
of these insects: they are haplo-diploid.
• Males are haploid, that is, the males have
only a half-complement (one copy each) of
chromosomes (they develop from
unfertilized eggs).
• But the females are diploid, having the
usual two copies of each chromosome.
Evolution of social behaviour
• This is important to understanding why so many
of these insects are social (and their social
behaviour has, in many cases, arisen
independently).
• By contrast, insects that are diploid have only
produced one line of social insects (the
termites).
• Aside: there is one odd species of mammal that
is social in a rather similar way (the naked mole
rats).
Relatedness and resources
• Because they are haplo-diploid, female
bees and ants and wasps are genetically
more similar to their sisters (75%) than
they are to their own offspring (50%).
• But the males’ genes are 100%
represented in their offspring, and only
50% represented in their sisters.
• So it’s hardly surprising that the males
don’t do much around the colony!
Intentional language
• Gould self-consciously distances himself from
the (ubiquitous) talk of ‘he would rather’ or ‘she
prefers’ in this evolutionary context:
• “I do not mean to attribute conscious will to
creatures with such rudimentary brains. I use
such phrases as “he would rather” only as a
convenient shortcut for “in the course of
evolution, males who did not behave this way
have been placed at a selective disadvantage
and gradually eliminated.” ”
The argument from investment
• The force of this kind of selection appears in the sexratios and weight-ratios of male and female offspring.
• The queen, who has an equal shot at reproducing
through her daughters and her sons, produces equal
numbers of both. (A selective account of this can be
given, if open competition for mates is assumed.)
• The workers are more closely related to the daughters,
and feed them preferentially, producing about a 3:1
weight ratio in favour of the daughters.
• But slave workers don’t discriminate, and so produce a
1:1 weight ratio (except when working in their own
colony instead of for the slave-making ants).
Very interesting, but…
• What does this tell us (if anything) about our own social behaviour?
• First, that our altruistic, kind side is just as natural as our violent,
aggressive side.
• Second? Not much more than this.
• Here, Gould sets his heels and resists the temptation to apply
sociobiological ideas to interpret human societies in any greater
detail.
• He recognizes our genetics as allowing a wide range of potential
behaviour, from the extremely aggressive and selfish to the
extremely self-sacrificing.
• But this genetic potential is best understood, Gould thinks, in terms
of flexibility, a rich range of possibilities, rather than in terms of
specific ‘rules’ we tend to obey.
• So for Gould we are even less like ants than Ruse and Wilson
suppose. (I’m inclined to think that’s a good thing…)
Homosexuality
• Wilson’s hypothetical explanation of (exclusive)
homosexuality:
– This is an evolutionary dead end for the individual.
– But if the individual is able, thereby, to contribute
substantially to the success of his/her relatives in
raising children, that problem is potentially solved.
– So in principle, there could be (at some level of
frequency) selection for a gene that normally gives
rise to exclusive homosexuality.
A risky strategy
• Gould praises Wilson’s aim, which is to argue that for
some people homosexuality may be entirely natural and
that therefore we should not condemn it or them.
• But he thinks the ‘natural therefore not to be condemned’
move is risky- what if it turns out that there is no ‘gay’
gene? Is it OK to revert to mistreating homosexuals?
• Instead, Gould proposes that the defense of civil rights
for homosexuals should rest on familiar normative
grounds: This is private, consensual behaviour in which
both parties are adults and able to make their own
choices.
• Here Gould is echoing Huxley (recall the ‘no better
reason than we had before’ remark).
Determinism
• The contrast between ‘gene-behaviour’
determinism and Gould’s emphasis on the
lability of human nature is subtle, but substantial.
• The ‘epigenetic rules’ account isn’t strictly
speaking deterministic– our genes, on such a
view, don’t fix our behaviour patterns, but they
bias them strongly in particular ways, and
normally result in certain particular behavioural
patterns.
• Further, it suggests that these patterns are
adaptive in particular ways.
Biological Potentiality
• Gould, however, thinks that our behaviour is much more
flexible (at these levels).
• So we can pick up and learn and alter behavioural
patterns.
• Moreover, the kinds of patterns Ruse and Wilson
imagine as ‘built in’ and the result of selection may
instead be the result of social evolution.
• No genes need to be exchanged in order for a group to
take up (say) the use of iron as an important material for
tool-making.
• Instruction and learning by example allow for much more
rapid spread of advantageous behaviour patterns (and
sometimes perhaps for less advantageous ones– think
of fads, and worse…).