[MUSIC] How are we going to tell the story of the living earth? In particular, how are we going to tell the story of earth to our children? This is especially important because in the last couple of centuries, we have learned more about the earth than in perhaps the previous100,000 years. So the question is how are we going to convey that, the essence of that ,to the next generation? One thing is completely clear, the Earth is very different than what we thought. The Earth is not a platform, it's not a background. In fact, the great discovery is this. Life doesn't exist on top of the earth. Life is a partner to the oceans, to the atmosphere, to the land. For instance, if we look at the atmosphere, it is 21% oxygen. This makes us unique among all the known planets. The only reason we have oxygen in our atmosphere is that life is pouring out forth each day. So the very composition of our air is the fact that life is here. In that sense, life is moving into the atmosphere. [MUSIC] But an even more radical hypothesis is beginning to emerge in the minds of some scientists, [MUSIC] Perhaps Earth is not only and integrated system. Perhaps Earth somehow maintains itself, so that life can flourish. Consider temperature, life only exist in a very narrow band of temperature. So something like this temperature has been true of earth for 4 billion years [MUSIC] Now, scientists originally thought this was because the Earth just happened to be 93 million miles away from the Sun. But during the 1950s, we learned about the fusion processes taking place in stars. And so now we know the sun's temperature, has increased by over 25%, over the last 4 billion years. [MUSIC] Which means somehow, earth has had to adapt itself to maintain that stable narrow ban of temperature. How? We know some of the details. Early Earth had a 1,000 times the carbon dioxide as present day Earth. So during that time, the Earth's system has drawn the carbon dioxide out of the atmosphere, forming for instance shells of marine algae. And then when the marine algae die, the shells go to the bottom of the ocean. So more and more carbon dioxide's taken out of the atmosphere, which enables the Earth to cool down while the Sun heats up. But the question returns, is all of this being organized by the Earth as a whole so that life could flourish? If that's the case, then the atmosphere is not just stuff. It's something like a membrane and we are not living on an earth. We are actually participants in a vast intricate system that is something, like a living cell. [MUSIC] A living cell has the power to learn through time. This is what distinguishes the first cells from all of the other beings that existed prior to life's emergence. A star for instance has the power to organize itself for billions of year. But throughout that time, it never needs to learn anything new. [MUSIC] Life learns. For life can adapt itself to new situations by changing its form and by remembering these changes. Life remembers the past by storing information in its DNA molecules. It is this power of memory, encased in each living cell, that enables life to learn and thus evolve. [MUSIC] One of the ways in which to understand the nature of life's memory Is by using the ideas of the mathematician philosopher Pythagoras. You know a number of Pythagoras as ideas were revolutionary. And like a lot of revolutionary ideas, they weren't that popular. In fact, Pythagoras had to hide from the tyrant Polycrates, who is in charge of Samos. And tradition has it, this is where he hid, right here halfway up the mountain, the cave there. One of Pythagoras's central convictions was that the essence of life is not air or water or fire, as the other Greek philosophers taught. Rather, the essence of life is number, pattern. It seems such an odd idea. I mean life is so sensuous, it's so complex, so rich. How can the essence of that be something abstract like number or pattern? [MUSIC] It is precisely this deep connection between life and pattern. That enables life to remember its crucial achievement. That's what DNA does. In the precise sequence of the nucleotides, DNA holds the essence of life. [MUSIC] Life cannot hand down the actual molecules to my body. Instead, life handed their essence in the form of genetic information. Because of this, our bodies can come alive a thousand different ways each day. [MUSIC] Life has learned to learn. [MUSIC] One of the central ways of learning for our species involve seeing. Life has invented so many different ways of seeing. The amazing thing is this process is not yet over. Come with me into Pythagoras' Cave. [MUSIC] Beginning billions of years ago, the earliest cells began to develop a sensitivity to light. They can sense it and move toward it.. And it was this capacity that lead eventually to the development of the eye. Now the first eye for which we have any fossil evidence is that of the trilobites, 500 million years ago. The trilobite, intent upon piercing through the darkness, invented an eye using calcite, a mineral. [MUSIC] The trilobite was able to see only in the direction of these rods. A primal form of seeing that proved so successful, we find it even now in the compound eyes of flies and lobsters. [MUSIC] And entirely different form a scene was invented by the worms and carried forward by the fish. [MUSIC] This type of virus the one we know best for it's the one we inherited the water-based eye [MUSIC] Even after 500 million years, eyesight continues to evolve. In humans, power of seeing deepens with a new kind of sight, insight. We see on the inner screen of our imaginations. Life has learned yet another way of seeing. One with the power to transform everything. [MUSIC] With this new way of seeing, we find ourselves blinking in a thrilling and yet unsettling light. [MUSIC] Rooted in the center of immensities, we open our eyes and see each thing anew. Each thing ablaze with cosmic creativity, millions of years old. [MUSIC] With the insights made possible with conscious self awareness. Our vision now stands back through billions of years of evolution. [MUSIC] We see not only the scurrying spider, but the entire cosmic journey layered into the spider's body. Including even the distant stars, out of whose explosions its molecules were constructed. [MUSIC] At this capacity to see into the depths of time gives new meaning to death. [MUSIC] The universe throughout space and time is filled with violence and chaos. Millions of galaxies have been destroyed. [MUSIC] Trillions of animals have been killed. [MUSIC] Death and suffering are woven into the very heart of the universe. [MUSIC] Usually such destruction is massive and senseless. A volcano erupts and kills every living being in its vicinity. [MUSIC] But it could also happen that dealing with death leads to more complex coevolutionary relationships. [MUSIC] For a rabbit, an eagle were the face of destruction. [MUSIC] But in this relationship, the eagle develops more acute eye sight and the rabbit develops greater speed for escape. [MUSIC] Interdependent communities arise out of suffering and death. [MUSIC] The ultimate meaning of this escapes easy explanation. [MUSIC] We are confronted with the fundamental mystery in which the small self of the individual dies in to a nourish the whole community. [MUSIC] But living beings are not just linked together by food. [MUSIC]
