Dear Prof. Diamond,

I’ve just read “The Third Chimpanzee”, which strikes me as being a  particularly important book. It taught me a lot and made a strong impression on me - not least because independently, though with far less scholarship, I have been thinking along very similar lines myself.

My name for the “Third Chimpanzee” is the planet’s “Greatest Ape”, which is meant as a humorous jibe, of course, but like your expression, is primarily concerned with emphasising the neglected importance of man’s animal nature and origins.

Although many people know and claim to accept Darwin’s theory of evolution, including our own animal origins, for most I do not think the implications have even begun to sink in. We continue to flatter and deceive ourselves into believing that we actually deserve the name, Homo sapiens (wise man), given to us by 18^th Century science, when Homo stupidus or Homo, plus whatever the Latin word for “blind” is, would be far more appropriate, serving to remind us of what we actually are (the planet’s “Greatest Ape”) and of our limitations, instead of promoting illusions regarding the extent and effectiveness of human knowledge and rationality, our vanity, and aspirations for limitless possibilities and wealth.

Another important insight, which fits in well with what you write, but which I don’t think you mention in your book, is how the recent rise of human civilisations has shifted the individual’s focus in the struggle to survive and prosper from the natural environment to an artificial, socio-economic environment, which nowadays to a very large extent boils down to making, or having a source of, money. To the individual or group of individuals (whether a family, company or a whole nation state), exactly how they make their money is irrelevant (generally provided it is legal, more-or-less); the essential thing is that we have it, since experience teaches us that money will buy whatever we need to survive and prosper, and more.

And who am I, presuming to be less blind and stupid than others? No doubt, I too am (perhaps even more) stupid and blind (than others) in my own ways, but like Socrates, who knew that he knew nothing, I know it.

If we (i.e. our children and coming generations) are to survive, we have to make some radical changes to our behaviour. As you say in your book, we have the ability to do it; our situation is not hopeless. What we lack is the will, and we lack that because we lack the necessary level of awareness of just how serious and urgent our situation is. And there are mighty forces working against us becoming aware; like a patient with the symptoms of a life-threatening disease, which he doesn’t want to face up to, and whose doctors (politicians and those running the economy) assure him anyway that there is nothing, at least nothing too serious, to worry about.

Our animal  nature works against us here too, because it programs and conditions us to accept what is “normal” as being okay, or at least not too bad – no matter how insane it might be in reality, even if it is leading to our downfall and demise from the planet.

The central problem is that our inherently non-sustainable, growth-dependent economy and grossly materialistic, equally non-sustainable lifestyles are based (and dependent on) our “more animal than human” nature. How could it be otherwise, considering our animal origins? But because they are so familiar to us (quite apart from our dependency on them), be cannot help seeing them as being perfectly “normal” and okay.

It is relatively easy for you, with your professorship and a vocation that not only provides you with money to support yourself and your family, but also, I am sure, with a great deal of job satisfaction. The vast majority of people are not so fortunate, but have to “make a living” for themselves and their families the best way they can, even if that means doing things that will ultimately lead to our extinction. Again, to our animal eyes, whatever we do individually seems, and in fact is, utterly insignificant, just a proverbial drop in the ocean. Like so much else, we "know" but still fail to really understand that the drops add up and will eventually fill the ocean. We understand the devastating effect that our collective behaviour is having on the planet, but have great difficulty equating it with what we do as individuals.

Individual motorisation and frequent air travel, for example, are firmly entrenched in our lifestyles, or if not, in our aspirations, the economy and millions of jobs are dependent on them, yet on a global scale both are utterly unsustainable, are already placing too great a drain and strain of Earth’s limited resources and carrying capacity.

We are like an addict, still in denial of our addiction and dependency (to a non-sustainable economy and ways of life) and of where it is leading us (to extinction).

For our children’s sake, if not for our own, we have to face up to it.

We have to initiate the greatest and most rapid revolution in human history (the 20^th Century should have taught us how not to go about it).

Otherwise, our children and grandchildren may well not survive; and those who do will curse us for trashing our (and their) unique, beautiful and (still) bountiful planet.

We have to make fundamental changes to our economy and lifestyles, or rather, to the values, attitudes and aspirations on which they are based, and create alternative, sustainable economies and more humane and enlightened, far less materialistic, lifestyles, based not on the drives and blind self-interests of our “more animal than human” nature, but on the enlightened self-interest of our more human (more godly?) nature.

Judging by the epilogue of The Third Chimpanzee (which granted was written a long time ago now), not academically, but economically you still seem to have both feet firmly planted in existing, non-sustainable society. If you are not already doing so, what about helping to create a fair, humane and sustainable alternative, into which, sooner rather than later, we can both place at least one of our feet. Our children and grandchildren will have to complete the revolution, with both of their feet firmly placed in a fair, humane and sustainable socio-economic order.