The book and the man
Richard Dawkins is the author of many "popular science" books on zoology and ethology (in this context, the study of animal behavior). These include The Blind Watchmaker (in which Dawkins sets out to answer the question "Why do we exist"?), River Out Of Eden (which sets out to explain evolutionary concepts in simple terms), Climbing Mount Improbable (in which Dawkins sets out to explain why things which are often regarded as too complex to have evolved can have done) and most recently A Devil's Chaplain (a collection of selected writings). But probably most famous is The Selfish Gene, which was first published in 1976. In it Dawkins tackles some very controversial questions in ethology - primarily questions of aggression and altruism. In doing so explains biological and Darwinian concepts in a manner which are intelligible to the general reader, conceptualising everything brilliantly.
One of Dawkin's primary weapons in the battle for your mind is his passion. It's clear he loves his subject dearly and believes passionately in the views he espouses - and indeed, since The Selfish Gene was written it has become the stuff of textbooks. The idea itself owes to the writings of, in particular George C. Williams, specifically Adaptation and Natural Selection. Other authors who Dawkins acknowledges throughout the book are W. D. Hamilton, John Maynard Smith and Robert Trivers. I will now trace through Dawkin's arguments in a rudimentary fashion which is designed to give you a taste for the book itself.
Replicators and genes
Dawkins starts out by proposing a theory of the origin of life. It is one of many (in The Blind Watchmaker he uses a different one based on inorganic silicates, proposed by Graham Cairns-Smith) but one which he explains very well and is particularly useful in the conceptualisation that follows in the rest of the book. For the benefit of us non-science types, it includes the well-known phrase "primordial soup". This "primordial soup" can be imagined to be a mass of different molecules which it is thought existed on the baby Earth (molecules like water, methane, ammonia which are on other planets in the Solar System). Agitated by the energy of the Sun or by volcanic activity, these molecules gradually join into more complex ones (a much simpler process has been tried in conical flasks and resulted in simple amino acids). Over an amount of time incomprehensible to the human mind, a particular type of molecule was formed - Dawkins calls it the Replicator. The Replicator had one very interesting feature - it could "make" copies of itself.
Naturally, no volition is involved. It just happens that some molecules attract molecules of the same type, and if a chain of such molecules is formed, it will make a copy of itself which could then break away. Or they could form in layers as crystals do. This is of course very improbable, but it only had to happen once - from that point onwards the Replicator could happily churn out copies, which would churn out new copies, etc. Suddenly, a new type of stability is in the world - the building blocks, the component molecules, of the Replicators are all about it in the "primordial soup", and naturally over time the "population" of molecules in the soup will come to be composed more and more of the Replicators. Replicators that were particularly good at making accurate copies of themselves fast would be even more dominant. Some Replicators might even be able to "break down" and "eat" (ie. form into new copies of themselves) over types of Replicators. These molecules are just obeying the laws of physics, but gradually the soup would contain ones which were most capable of exploiting the laws of physics to their own advantage.
Gradually, the soup of molecules would be used up, that is become part of stable structures. Replicating was becoming a tough business. Then, by chance, a Replicator managed to attract a "wall" of protein around itself. This protected itself from being broken down by the carnivore Replicators that would make copies of themselves from its component parts if it drifted too near. It could happily make copies of itself within its little "survival machine". This could well have been how the first proto-cells developed.
DNA, Dawkins says, may or may not be like these early Replicators. It doesn't matter. What matters is the principle - the principle is that the Replicators built up "survival machines" around them. These survival machines eventually became more complex, and split into two main groups - animals and plants. Plants "learnt" how to exploit the light of the Sun and produce energy from it - and animals "learnt" to exploit this by eating the plants, or each other. Organisms were becoming more and more complicated, but their nature was still dictated by the DNA in their cells. As is well known, almost every cell in an organism's body contains a complete "copy" of its DNA. Half of this material comes from its mother, and half from its father. We hear of "genes" being passed from parent to child, but it is less well-known that "gene" is not as precisely-defined term as it sounds. Dawkins describes it thus (this is important) -
"a genetic unit that is small enough to last for a large number of generations and to be distributed around in the form of many copies"
DNA is made up of a series of molecules which are known by letters - A, T, C and G. When a sex cell - a sperm or egg - is created, it has exactly half of its begetter's genetic material. This process randomly takes different lengths of genetic units and combines them in new DNA strings. This means that particularly large series of molecules in my father's DNA might have being broken down into smaller bits, rearranged altogether, or had boundaries cut across in their transfer to me. This means that large strings of molecules are not likely to survive across generations - smaller ones, however, do (say a particular "genetic unit" makes up 1/100th of a chromosome - it is more likely not to be split up than the genetic unit which comprises 1/2th of the chromosome). Genetic units such as this have the capability to exist for many millions of years, whereas the survival machines they exist within are only temporary expressions of an aggregate of genes.
Survival machines and genes
There is a very old argument in evolutionary biology, the argument of nature vs. nurture. And, while reading Dawkin's work, it's worthwhile to forget all about it. This isn't what it's about. Clearly, environmental factors have a bearing on how an organism will act, insofar as they effect how it is capable of acting - for instance, it may have stunted growth due to lack of food in its youth. But I digress.
Genes do not control how we act on a second-by-second basis. There is no gene which exists to make me write this write-up. But genes did make something in their survival machines that vastly improve its survival chances and dictate its action on a moment-by-moment basis - the brain. And insofar as they influence the creation of the brain, the neurones, and the muscles (the means of interacting with the environment), genes endow their survival machines with survival qualities. The senses help organisms know when to act to their benefit - for instance, there's no use chewing if there's no food in your mouth. The true utilisation of the brain came with the invention of cognitive simulation - the ability to predict what will happen if a certain action is taken, and perform a cost benefit analysis of the outcome. In this way an organism is able to "act out" in its brain various courses of action in a given circumstance, and work out the odds of it getting a pay off from each one. Dawkins describes survival machines as a sort of "gambler", whose genes indirectly - through the formation of the brain and the body - endow it with the ability to take risks that will help in the propagation of its offspring, and hence its genes. This is not an act of volition on the part of the genes, it is merely a logical extension of what we started with - replicators that, by influencing the environment, tend to make copies of themselves. DNA is the master of this, and genes which tend to produce good survival characteristics tend to beget copies of themselves in their survival machine's offspring (which will be numerous).
The heart of the "selfish gene" theory
In questions of human society we often think almost exclusively in terms of the good of groupings of people - what will be good for our family, our community, or for society. We are certainly aware of the fact that this is how it is considered "proper" to think. And one common misconception which must be cleared up immediately is that The Selfish Gene does not say it is "proper" to think selfishly, or to ignore the cares of your family, your community, or your society. As Dawkins says, there is a distinct difference between writing a book on the way you believe things to be and how you think they "ought" to be in some abstract way - nor does the selfish gene theory even imply that human beings are, or should be, "selfish". Just as Darwin had no way of anticipating the so-called "social Darwinists", nor is Dawkins responsible for any such manipulation of his work.
Before we continue it is necessary to define a few terms. The first is "altruism", a term which is to be shed of any moral implication - it means, simply stated, an action taken by an animal which increases the survival of another animal to the detriment of its own. The benefit - or detriment - may be marginal (if I am in urgent need of CPR, it is of little detriment to someone to give me it, but the benefit to myself is obviously huge). Altruism had been used by many biologists to propose the theory that animals act for the "good of the species". Whilst this appeals to common sense, an evaluation of it seems to suggest it is unlikely. Firstly, why stop at the species? Why don't organisms act for the good of the genotype? What about for the good of all survival machines? It is clear that all organisms are competing with each other for limited resources (this is particularly intense between members of the same species, often different species can co-exist very well), and when we consider the basic unit of replication - the gene - something becomes even more clear. What is in fact happening, remember, is that the genes are influencing their survival machines - indirectly, through the pre-programming - to propagate themselves.
Combinations of genes tend to make particular Evolutionary Stable Strategies. This is defined as being a survival strategy that "works" - say, being a worm - and keeps on working for a vast period until a significant change in the environment or a radical new organism appears. Small mutations don't scare the ESS, because it's the most stable worm in the ground - it has just the right quantity of aggression, of altruism, of everything, to survive in favour of different quantites of these properties. More aggressive worms might appear and waste all their energy in internecine conflict, whilst the "doveish" worms quietly get along with life, occasionaly suffering a minor penalty for having to run away from an aggressive worm. Eventually, the aggressive worms will die off and only the ESS will remain (Dawkin's illustrates this using game theory, but I'm not going to get into that).
So if the basic unit of evolution is the gene, and the survival of the fittest is in fact the survival of the fittest genes, how do we explain altruism at all? Why don't animals go to the opposite logical extreme - engaging in a murderous rampage, killing - and preferably devouring - everyone in their sight, including members of their own species? Explaining this is the core of Dawkin's work, and I provide only a brief overview here.
Aggression. Why are organisms only selectively aggressive? Aggression takes energy, and any organism engaging in it runs the risk of death. Before engaging in aggression it will have to carefully weight up the pros and cons of its action and decide whether it's worth it. What are the risks? What are the rewards? Constant aggression costs energy and might even eliminate other survival machines that you might be able to have a symbiosis with. Too much doveishness can result in being dominated by hawks.
Family. Dawkins examines how organisms look upon others that share their genes. An organism's brother has half of its genes, as does its mother. If it can act to help them with marginal cost to itself, its genes have helped propagate themselves. The link becomes more tenuous with cousins and distant relatives, and so animals become less willing to risk their lives for others. Dawkins examines the critical question of whether organisms can recognise their kin, and how the "mathematics" of their gambling might take form.
Generations. Do organisms have favourite offspring, as in ones they invest more of their pressure energy in? Why? And what dictates how many offspring a female will want to have? Attacking theories based on the "good of the species" that suggest animals keep their offspring down for the good of all, Dawkins suggests that, as always, this behavior is rooted in the selfish gene. Having plenty of children in a time of over-crowding is obviously not going to be good for those children - it is much better for an organism to look after a few children very well, hence ensuring the propagation of its genes.
Symbiosis. Why do animals live in flocks and groups? When birds pick the tics from each other's heads, are they doing it for their own benefit (the chance the other bird will reciprocate) or for the "good of the species" - you can guess Dawkin's answer to this by now! In a chapter on the Prisoner's Dilemma Dawkins draws on the research of Robert Axelrod to show that even with selfish genes, "nice guys can finish first".
I provided the basis of the logic behind Dawkins' book and some of the conclusions. I hope I've encouraged you to read what is a very fine and intelligible piece of literature, and one which really makes "popular science" respectable.