There is a kind of terrible irony that at the point that we are best able to understand and appreciate and value the richness of life around us, we are destroying it at a higher rate than it's ever been destroyed before. And we are losing species after species after species, day after day, just because we're burning the stuff down for firewood. And this is a kind of terrible indictment of our understanding.

But, you see, we make another mistake, because we think somehow, this is all right in some fundamental kind of way, because we think that this is all sort of "meant to happen".

Now let me explain how we get into that kind of mindset, because it's exactly the kind of mindset that the kakapo gets trapped in. Because, what has been a very successful strategy for the kakapo over generation after generation for thousands and thousands of years, suddenly is the wrong strategy. And he has no means of knowing, because he is just doing what has been successful up till then. And we have always been, because we're toolmakers, because we take from our environment the stuff that we need to do what we want to do and it's always been very successful for us--

I'll tell you what's happened. It's as if we've sort of put the "pause" button on our own process of evolution, because we have put a buffer around us, which consists of medicine and education and buildings, and all these kinds of things that protect us from the normal environmental pressures. And, it's our ability to make tools that enables us to do this.

Now, generally speaking, what drives speciation, is that a small group of animals gets separated out from the main body by population pressure, some geographical upheaval or whatever. So imagine, a small bunch suddenly finds itself stranded ina slightly colder environment. Then you know, over a small number of generations that those genes that favor a thicker coat will come to the fore and you come back a few generations later, and the animal's got a thicker coat.

Man, because we are able to make tools, we arrive in a new environment where it's much colder, and we don't have to wait for that process. Because we see an animal that's already got a thicker coat and we say we'll have it off him. (Laughter.)

And so we've kind of taken control of our environment, and that's all very well, but we need to sort of be able to rise above that process. To rise above that vision and see a higher vision--and understand the effect we're actually having.

Now imagine, if you will, an early man, and let's see how this mindset comes about. He's standing, surveying his world at the end of the day. And he looks at it and things, "This is a very wonderful world that I find myself in. This is pretty good. I mean, look, here I am, behind me is the mountains, and the mountains are great. Because there are caves in the mountains where I can shelter, either from the weather or from bears that occasionally come and try to attack me. And I can shelter there, so that's great. And in front of me is the forest, and the forest is full of nuts and berries and trees, and they feed me, and they're delicious and they sort of keep me going. And here's a stream going through which has got fish in it, and the water's delicious, and everything's fantastic.

And there's my cousin Ug. And Ug has caught a mammoth! Yay!! (Clapping). Mammoths are terrific! There's nothing greater than a mammoth, because you can wrap yourself in fur from the mammoth, you can eat the meat of the mammoth, and you can use the bones of the mammoth, to catch other mammoths!

Now this world is a fantastically good world for him. And, part of how we come to take command of our world , to take command of our environment, to make these tools that we need, is that we ask ourselves questions all the time. So this man starts to ask himself questions. "This world" he asks himself, "so, who made it?" Now, of course he thinks that, because he makes things himself, so he's looking for someone who will have made this world. "So, who would have made this world?" he thinks. "Well, it must be something a little bit like me. Obviously much much bigger, and (glancing up) necessarily invisible, but he would have made it. Now, why did he make it?"

Now, we always ask ourselves "why" because we look for intention around us, because we do things with intention. We boil an egg in order to eat it. So, we look at the rocks and we look at the trees, and we wonder what intention is here, even though it doesn't have intention. So we think, what did this person who made this world intend it for. And this is the point where you think, "Well, it fits me very well. You know, the caves and the forests, and the stream, and the mammoths. He must have made it for me!"

I mean, there's no other conclusion you can come to. And it's rather like a puddle waking up one morning--I know they don't normally do this, but allow me, I'm a science fiction writer (laughter). A puddle wakes up one morning and thinks "Well, this is a very interesting world I find myself in. It fits me very neatly. In fact, it fits me so neatly, I mean, really precise, isn't it? (Laughter) It must have been made to have me in it!" And the sun rises, and he's continuing to narrate the story about this hole being made to have him in it. The sun rises, and gradually the puddle is shrinking and shrinking and shrinking, and by the time the puddle ceases to exist, it's still thinking, it's still trapped in this idea, that the hole was there for it. And if we think that the world is here for us, we will continue to destroy it in the way in which we have been destroying it, because we think we can do no harm.

There's an awful lot of speculation one way or another at the moment, about whether there's life on other planets or not. Carl Sagan, as you know, was very keen on the idea that there must be. The sheer numbers dictate, because there are billions and billions and billions, as he famously did not say, in fact, of worlds out there, so the chance must be that there's other intelligent life out there. There are other voices at the moment saying that if you look at the circumstances here on earth, they are so extraordinarily specific that the chances of there being something like this out there, are actually pretty remote.

Now, in a way it doesn't matter. Because think of this--Carl Sagan, I think, himself, said this. There are two possibilities: either there is life out there on other planets, or there is no life out there on other planets. They are both utterly extraordinary ideas! But, there is a strong possibility that there isn't anything out there remotely like this. And we are behaving as if this planet, this extraordinary, utterly, utterly extraordinary little ball of life, is something we can just screw about with any way we like.

And maybe we can't. Maybe we should be looking after it just a little bit better. Not for the world's sake--we talk rather grandly about "saving the world". We don't have to save the world--the world's fine! The world has been through five mass extinctions. Sixty-five million years ago when, as it seems, a comet hit the earth at the same that there were vast volcanic eruptions in India, which saw off the dinosaurs, and something like 90% of the animals on the planet at the time. And another 150 million years earlier than that, another giant, giant, giant extinction. The world has been through it many times before, and what tends to happen, what happens invariably after each mass extinction, is that there's a huge amount of space available, for new forms of life suddenly to emerge and flourish into. Just as the extinction of the dinosaurs made way for us. Without that extinction, we would not be here.

So, the world is fine. We don't have to save the world--the world is big enough to look after itself! What we have to be concerned about, is whether or not the world we live in, will be capable of sustaining us in it. That's what we need to think about. Thank you very much, ladies and gentlemen. (Applause).