This is my summary of the first three chapters of The Blind Watchmaker
Introduction
-following on from "The Selfish Gene"
-Applications of Darwinism
-Fueling the creation vs Evolution debate
-problems of the debate lies in the complexity of design of all life
-we are on the wrong time scale, we look at lifetimes when we should
look at thousands of years.
-Because we are creative beings we like to imagine that everything is
created.
Chapter 1 - Explaining the very improbable.
Humans are very complex beings made up of thousands of different
systems. We are built for hunting, feeding mating and child rearing. And
then we ask this difficult question "Why do we exist?" We assume there
is a designer. Title of book from William Paley's book of 1802 which
argues for a creator of such a complex world, like a watch has a
creator. Dawkins claims that if there is a watchmaker then he is blind
as there is not ultimate purpose in evolution.
The improbablity of a certain event happening is lessened with
hindsight. There is no less chance that a certain combination of lottery
numbers will be drawn than another set of numbers. All sets of numbers
have the same probablity with hindsight and so are not any more
miraculous than the next set of numbers. However Dawkins comments
"However many ways there may be of being alive it is certain that there
are more ways of being dead " Pg 9
Dawkins then comments on the importance of looking at all levels of
explination to explain how something works. It is necessary to look at
all the componant parts and the sum of the total parts. He used William
Paley's example of an eye to illustrate this and to lead into the next
chapter.
Chapter 2 - Good design
" Natural selection is the Blind watchmaker, blind because it does not
see ahead, does not plan consequences, has no purpose in view" Pg 21
The design of a body is good if it does what it needs to do to acheive
soem purpose, e.g. eating, reproducing. He then spends the rest of the
chapter using the example of the radar system of bats which is highly
complex in using sonar. He does this in order glorify the "prodigious
works of nature" and to agree with Paley in this. The question "How
could an organ as complex as an eye evolve?" is stupid. It has because
of necessity and evolutionary time. This is not evidence for a creator.
Chapter 3 - Accumulating small change
"Each successive change in the grdual evolutionary process was simple
enough relative to it's predecessor" Pg 43
Changes occur with a process like seiving. A category is chosen e.g. the
size of a hole and objects are sorted according to this, e.g. stones are
small and fit through the hole or are too big and don't. These small
stones can then be seived again so that a different category os chosen.
Evolution is like this, cummulative selection not single step
selection. Cummulative selection takes the products of the last
selection and goes on.
Dawkins illustrates that everything is possible in time. Even a monkey
typing "methinks it is like a weasel" is possible given enough time. If
certain errors occur and are chosen, a computer can "generate" that
sentance through random sequences of words and cummulative selection, in
64 generations. Darwinian selction is cummulative and therefore not
random as choices are made according to the environment.
Dawkins then talks about a computer programme which he created which
writes a programme simulating splitting cells. One single line will
"breed" more lines and sequences can be seen. By then programming in
random "mutations" to slightly change the reproductive pattern, many
variations of pictures are drawn, each very different although
differing from it's Parent by only a little. (It is best to look at the
pictures in the book to see the examples of this as it will be
clearer.)He calls all theses different variations of the programme
"boimorphs" and describes how they are all linked in "animal space" that
is they are all mutations of the same pattern but there are thousands of
different possibilities. This single step variation is shown in the
similarity between parents and offspring
"the number of ways of being dead is greater than the number of ways of
being alive; chances are very high that a random jump in genetic space
is pretty likely to end in death. But the smaller the jump, the less
likely death is, and the more likely it is that the jump will result in
improvement."
This leads on to Chapter 4 which describes examples of single step
evolution.
Kate Lyne
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