Hi, I'm Tim Tyler, and today I'll be discussing some of the
misunderstandings of cultural evolution which I once laboured under.
This is, essentially, a confession video, where I publicly parade the
history of my own confusion.
My motivations are mostly:
I want to publish my misunderstandings - so that others may avoid them;
I want to record my misunderstandings, while I can still remember
them, so I have a record of them which might help me to avoid similar
problems in the future;
Firstly, a brief history: my introduction to cultural evolution came
with reading The Selfish Gene - in 1985.
The next major injection of such material was Gary Cziko's book
entitled: Without Miracles. I liked Without Miracles
enough to
write a review of it in 2002 - a compliment which I rarely pay a
book.
It was more of an excuse to grind my own axe on the subject than a
review - I put forward the idea that Gary had things backwards - and
that:
Rather than attempt to shoehorn science and technology
into the straitjacket of Darwinian selection, I would prefer that the
reverse approach be taken - namely that Darwinian selection should be
seen as a backwards and degenerate case of the search for
knowledge - which exists because it is prebiotically plausible, and can
"get off the ground" easily.
After writing this essay, it sat on my web site for six years. In
January 2008, I had reason to refer to it - and I reread it - to see
if it needed editing before I cited it. At the time, I thought
it stood up reasonably well. However, I noticed that the
idea I quoted above was one which was interesting and seemed to be
under-appreciated.
I thought about expanding on the theme - wrote the teaser for
A New Kind Of Evolution -
and began researching the existing literature on cultural evolution.
Somewhat to my surprise, my views underwent a fairly dramatic paradigm
shift as I looked into the issue - and instead of converging on a more
orthodox view, as my understanding deepened, my opinions seemed to
become increasingly unorthodox. It wasn't just me who hadn't
previously grasped this material - almost everyone I
discussed the matter with seemed to be in the dark about it - and
there was practically no mention of it in most textbooks on
evolution.
Though I had been interested in evolutionary biology for decades, it
hadn't previously occurred to me to consider cultural evolution very
deeply - and it turned out that I had several fairly major
misunderstandings of the phenomenon. What I was looking at turned out
to be significantly more exciting and revolutionary than I had
previously imagined it to be.
Next, on to my misunderstandings:
Evolutionary epistemology is associated with the
discredited work of Karl Popper
I reasoned something like:
Evolutionary epistemology is closely associated with the work of Karl
Popper; Popper's work is a poor represention of how science works;
therefore evolutionary epistemology is wrong.
Enthusiasts of cultural evolution often do seem to favour the work of
Karl Popper -
who presented an evolutionary epistemology of science
in his book The Logic of Scientific Discovery.
He suggested that scientific theories evolve, and sometimes
go extinct - through a process he called falsification.
However, few these days accept Popper's picture of science. Theories have
associated probabilities. Falsification is not much like death -
theories that do not conform to the data can be resurrected if that
data turns out to have been fabricated. "Dead" theories - such
as the idea of the
luminiferous aether and
the phlogiston theory of fire
live a zombie existence in the history books - and still play
some role in guiding scientific investigations from there.
I thought these issues reflected poorly on theories of cultural
evolution - since they represented a mismatch between how things work
in classical Darwinian evolution, and how they work in the evolution
of scientific theorise. They do reflect poorly on the version
of cultural evolution I had in mind at the time - but that view turned
out to be rather naive and simplistic.
My aha! moment on this issue came when I imagined the fate of
the information representing a scientific theory. I saw that
falsification was not the end of this information, and so the theory
was still alive, at least while it remained recorded in the
history books. Falsification was not a fatal blow to the associated
meme - but was better thought of as being a sticky label attached to it,
reading, "this theory is false".
Culture is not really "selected"
I reasoned that memes - like genes must be selected - or chosen.
However, ideas do not necessarily perpetuate themselves through being
chosen. So, ideas are not like genes in that respect.
This was another of my early problems with the idea of cultural
evolution. To illustrate it with an example:
A scientist might see from experimental results which include the
values of a function at 1, 2, 3, 7, 8 and 9 and that 5 is likely to be
the actual optimum value of that function. That is not conclusion that
involves a "selection" made from the previous trials - whereas
selection - in the form of a choice from proffered alternatives - is a
fundamental principle in traditional evolution.
I resolved this issue by deciding that choice from proffered
alternatives was not as fundamental to Darwinian evolution as I had
originally thought. Evolution does something more like rating
organisms than "choosing" them - since organisms can have multiple
offspring. Also, in sexual selection many organisms are not
really "chosen" rather they are the choosers.
David Hull attemped to deal with this issue by a radical redefinition
of the term "selection". I do not approve of that resolution - in my
view, it is better to taboo the term "selection" (in this context)
than to give the term an esoteric technical meaning that conflicts
with what it says in the dictionary.
Memes are replicators - but you can have evolution without replicators
I reasoned: memes are defined as being replicators; replicators are
unnecessary for evolution; and so you can have cultural evolution
without memes.
It turns out that I was not alone in observing this - it was one of
the five reasons cited by Henrich, Boyd and
Richerson for rejecting memetics in a 2002 paper, entitled "
Five Misunderstandings about Cultural Evolution".
The problem is with the premise: that memes are defined as
being replicators. Some people define memes as being
replicators - just as they define genes as being
replicators.
"Replicator" has strong implications of high-fidelity
informaion transmission. However, the condition required for an
evolutionary process is the sustained persistence of information via
copying. This need not necessarily be via high-fidelity
copying - as illustrated by John von Neumann's paper relating to the
synthesis of reliable organisms from unreliable components.
Since in practice, most genes and memes are replicators, this is a
rather abstract theoretical issue.
My solution is simply not to define genes and memes as being
replicators. Rather they consist of Shannon mutual information that
survives across multiple generations by copying.
Meme evolution is not part of biological evolution
I covered this issue in the "Misunderstood memetics" video. To recap,
if you consider evolution to be changes in the heritable
traits of a population over time, then according to that definition,
cultural evolution is part of biological evolution.
Inheritance via behavioural imitation is still inheritance.
Having a bone through your nose is still a trait.
For some reason, I didn't get this basic and fundamental
point originally. I thought of biological and cultural evolution as
largely separate, though linked, processes - with quite different
dynamics.
The memetics perpective is that they are a single process operating on
different types of replicator, which themselves have different
properties and propensities.
My embrace of memetics
An anecdote to close with:
After properly embracing cultural evolution, I kept memetics at arm's
length for a while, while considering my views on it. The main
bad things about it were, from my perspective:
The definition of a meme is mired in confusion - due to the issue
of whether genes only exist in brains or not. Having to repeatedly
explain my take on this issue whenever I mentioned memes seemed likely
to become tedious.
Also, I thought that the terminology was not really necessary. If
you use an information-theory definition of the term "gene" it's quite
possible to simply use "gene" and "genetics" to describe memetic
phenomena - and for some time I considered doing just that.
However, there are some benefits for having a single neat
term for a viral idea. I could hardly adopt Boyd and Richerson's
"cultural variant" terminology - that's simply a word-salad.
Also, I figured that if I did use the term "gene" to refer to concepts,
I would still frequently have to do a lot of
explaining before anyone understood what I was talking about - since
the information-theory definition of "gene" is not what most
people think of when you use the term. Whereas if I simply used the
term "concept", then any implied link biology would be lost.
So, at the end of the day - in the competition for the relevant niche
in my brain - the term "meme" eventually made it.
Here ends my list of my memetic misunderstandings. Enjoy!