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Until the End of Time

Mind, Matter, and Our Search for Meaning in an Evolving Universe

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NEW YORK TIMES BESTSELLER A captivating exploration of deep time and humanity's search for purpose, from the world-renowned physicist and best-selling author of The Elegant Universe.

"Few humans share Greene’s mastery of both the latest cosmological science and English prose." —The New York Times

Until the End of Time is Brian Greene's breathtaking new exploration of the cosmos and our quest to find meaning in the face of this vast expanse. Greene takes us on a journey from the big bang to the end of time, exploring how lasting structures formed, how life and mind emerged, and how we grapple with our existence through narrative, myth, religion, creative expression, science, the quest for truth, and a deep longing for the eternal. From particles to planets, consciousness to creativity, matter to meaning—Brian Greene allows us all to grasp and appreciate our fleeting but utterly exquisite moment in the cosmos.

1

The Lure of Eternity

Beginnings, Endings, and Beyond

In the fullness of time all that lives will die. For more than three billion years, as species simple and complex found their place in earth’s hierarchy, the scythe of death has cast a persistent shadow over the flowering of life. Diversity spread as life crawled from the oceans, strode on land, and took flight in the skies. But wait long enough and the ledger of birth and death, with entries more numerous than stars in the galaxy, will balance with dispassionate precision. The unfolding of any given life is beyond prediction. The final fate of any given life is a foregone conclusion.

And yet this looming end, as inevitable as the setting sun, is something only we humans seem to notice. Long before our arrival, the thunderous clap of storm clouds, the raging might of volcanoes, the tremulous shudders of a quaking earth surely sent scurrying everything with the power to scurry. But such flights are an instinctual reaction to a present danger. Most life lives in the moment, with fear born of immediate perception. It is only you and I and the rest of our lot that can reflect on the distant past, imagine the future, and grasp the darkness that awaits.

It’s terrifying. Not the kind of terror that makes us flinch or run for cover. Rather, it’s a foreboding that quietly lives within us, one we learn to tamp down, to accept, to make light of. But underneath the obscuring layers is the ever-­present, unsettling fact of what lies in store, knowledge that William James described as the “worm at the core of all our usual springs of delight.”1 To work and play, to yearn and strive, to long and love, all of it stitching us ever more tightly into the tapestry of the lives we share, and for it all then to be gone—­well, to paraphrase Steven Wright, it’s enough to scare you half to death. Twice.

Of course, most of us, in the service of sanity, don’t fixate on the end. We go about the world focused on worldly concerns. We accept the inevitable and direct our energies to other things. Yet the recognition that our time is finite is always with us, helping to shape the choices we make, the challenges we accept, the paths we follow. As cultural anthropologist Ernest Becker maintained, we are under a constant existential tension, pulled toward the sky by a consciousness that can soar to the heights of da Vinci, Shakespeare, Beethoven, and Einstein but tethered to earth by a physical form that will decay to dust. “Man is literally split in two: he has an awareness of his own splendid uniqueness in that he sticks out of nature with a towering majesty, and yet he goes back into the ground a few feet in order blindly and dumbly to rot and disappear forever.”2 According to Becker, we are impelled by such awareness to deny death the capacity to erase us. Some soothe the existential yearning through commitment to family, a team, a movement, a religion, a nation—­constructs that will outlast the individual’s allotted time on earth. Others leave behind creative expressions, artifacts that extend the duration of their presence symbolically. “We fly to Beauty,” said Emerson, “as an asylum from the terrors of finite nature.”3 Others still seek to vanquish death by winning or conquering, as if stature, power, and wealth command an immunity unavailable to the common mortal.

Across the millennia, one consequence has been a widespread fascination with all things, real or imagined, that touch on the timeless. From prophesies of an afterlife, to teachings of reincarnation, to entreaties of the windswept mandala, we have developed strategies to contend with knowledge of our impermanence and, often with hope, sometimes with resignation, to gesture toward eternity. What’s new in our age is the remarkable power of science to tell a lucid story not only of the past, back to the big bang, but also of the future. Eternity itself may forever lie beyond the reach of our equations, but our analyses have already revealed that the universe we have come to know is transitory. From planets to stars, solar systems to galaxies, black holes to swirling nebulae, nothing is everlasting. Indeed, as far as we can tell, not only is each individual life finite, but so too is life itself. Planet earth, which Carl Sagan described as a “mote of dust suspended on a sunbeam,” is an evanescent bloom in an exquisite cosmos that will ultimately be barren. Motes of dust, nearby or distant, dance on sunbeams for merely a moment.

Still, here on earth we have punctuated our moment with astonishing feats of insight, creativity, and ingenuity as each generation has built on the achievements of those who have gone before, seeking clarity on how it all came to be, pursuing coherence in where it is all going, and longing for an answer to why it all matters.

Such is the story of this book.

Stories of Nearly Everything

We are a species that delights in story. We look out on reality, we grasp patterns, and we join them into narratives that can captivate, inform, startle, amuse, and thrill. The plural—­narratives—­is utterly essential. In the library of human reflection, there is no single, unified volume that conveys ultimate understanding. Instead, we have written many nested stories that probe different domains of human inquiry and experience: stories, that is, that parse the patterns of reality using different grammars and vocabularies. Protons, neutrons, electrons, and nature’s other particles are essential for telling the reductionist story, analyzing the stuff of reality, from planets to Picasso, in terms of their microphysical constituents. Metabolism, replication, mutation, and adaptation are essential for telling the story of life’s emergence and development, analyzing the biochemical workings of remarkable molecules and the cells they govern. Neurons, information, thought, and awareness are essential for the story of mind—­and with that the narratives proliferate: myth to religion, literature to philosophy, art to music, telling of humankind’s struggle for survival, will to understand, urge for expression, and search for meaning.

These are all ongoing stories, developed by thinkers hailing from a great range of distinct disciplines. Understandably so. A saga that ranges from quarks to consciousness is a hefty chronicle. Still, the different stories are interlaced. Don Quixote speaks to humankind’s yearning for the heroic, told through the fragile Alonso Quijano, a character created in the imagination of Miguel de Cervantes, a living, breathing, thinking, sensing, feeling collection of bone, tissue, and cells that, during his lifetime, supported organic processes of energy transformation and waste excretion, which themselves relied on atomic and molecular movements honed by billions of years of evolution on a planet forged from the detritus of supernova explosions scattered throughout a realm of space emerging from the big bang. Yet to read Don Quixote’s travails is to gain an understanding of human nature that would remain opaque if embedded in a description of the movements of the knight-­errant’s molecules and atoms or conveyed through an elaboration of the neuronal processes crackling in Cervantes’s mind while writing the novel. Connected though they surely are, different stories, told with different languages and focused on different levels of reality, provide vastly different insights.

Perhaps one day we will be able to transit seamlessly between these stories, connecting all products of the human mind, real and fictive, scientific and imaginative. Perhaps we will one day invoke a unified theory of particulate ingredients to explain the overwhelming vision of a Rodin and the myriad responses The Burghers of Calais elicits from those who experience it. Maybe we will fully grasp how the seemingly mundane, a glint of light reflecting from a spinning dinner plate, can churn through the powerful mind of a Richard Feynman and compel him to rewrite the fundamental laws of physics. More ambitious still, perhaps one day we will understand the workings of mind and matter so completely that all will be laid bare, from black holes to Beethoven, from quantum weirdness to Walt Whitman. But even without having anything remotely near that capacity, there is much to be gained by immersion in these stories—­scientific, creative, imaginative—­appreciating when and how they emerged from earlier ones playing out on the cosmic timeline and tracing the developments, both controversial and conclusive, that elevated each to their place of explanatory prominence.4

Clear across the collection of stories, we will find two forces sharing the role of leading character. In chapter 2 we will meet the first: entropy. Although familiar to many through its association with disorder and the often-­quoted declaration that disorder is always on the rise, entropy has subtle qualities that allow physical systems to develop in a rich variety of ways, sometimes even appearing to swim against the entropic stream. We will see important examples of this in chapter 3, as particles in the aftermath of the big bang seemingly flout the drive to disorder as they evolve into organized structures like stars, galaxies, and planets—­and ultimately, into configurations of matter that surge with the current of life. Asking how that current switched on takes us to the second of our pervasive influences: evolution.

Although it is the prime mover behind the gradual transformations experienced by living systems, evolution by natural selection kicks in well before the first forms of life start competing. In chapter 4, we will encounter molecules battling molecules, struggles for survival waged in an arena of inanimate matter. Round upon round of molecular Darwinism, as such chemical combat is called, is what likely produced a series of ever more robust configurations ultimately yielding the first molecular collections we would recognize as life. The details are the stuff of cutting-­edge research, but with the last couple of decades of stupendous progress, the consensus is that we are heading down the right track. Indeed, it may be that the dual forces of entropy and evolution are well-­matched partners in the trek toward the emergence of life. While that might sound like an odd coupling—­entropy’s public rap veers close to chaos, seemingly the antithesis of evolution or of life—­recent mathematical analyses of entropy suggest that life, or at least lifelike qualities, might well be the expected product of a long-­lived source of energy, like the sun, relentlessly raining down heat and light on molecular ingredients that are competing for the limited resources available on a planet like earth.

Tentative though some of these ideas currently are, what’s certain is that a billion or so years after the earth formed it was teeming with life developing under evolutionary pressure, and so the next phase of developments is standard Darwinian fare. Chance events, like being hit by a cosmic ray or suffering a molecular mishap during the replication of DNA, result in random mutations, some with minimal impact on the organism’s health or welfare but others making it more or less fit in the competition for survival. Those mutations that enhance fitness are more likely to be passed on to descendants because the very meaning of “more fit” is that the trait’s carrier is more likely to survive to reproductive maturity and produce fit offspring. From generation to generation, qualities that enhanced fitness thus spread widely.

Billions of years later, as this long process continued to unfold, a particular suite of mutations provided some forms of life with an enhanced capacity for cognition. Some life not only became aware, but became aware of being aware. That is, some life acquired conscious self-­awareness. Such self-­reflective beings have naturally wondered what consciousness is and how it arose: How can a swirl of mindless matter think and feel? Various researchers, as we will discuss in chapter 5, anticipate a mechanistic explanation. They argue that we need to understand the brain—­its components, its functions, its connections—­with far greater fidelity than we now do, but once we have that knowledge, an explanation of consciousness will follow. Others anticipate that we are up against a far greater challenge, arguing that consciousness is the most difficult conundrum we have ever encountered, one that will require radically new perspectives regarding not just mind but also the very nature of reality.

Opinions converge when assessing the impact our cognitive sophistication has had on our behavioral repertoire. Across tens of thousands of generations during the Pleistocene, our forebears joined together in groups that subsisted through hunting and gathering. In time, an emerging mental dexterity provided them with refined capacities to plan and organize and communicate and teach and evaluate and judge and problem-solve. Leveraging these enhanced abilities of the individual, groups exerted increasingly influential communal forces. Which takes us to the next collection of explanatory episodes, those focused on developments that made us. In chapter 6 we examine our acquisition of language and subsequent obsession with the telling of stories; chapter 7 probes a particular genre of stories, those that foreshadow and transition into religious traditions; and in chapter 8 we explore the long-­standing and widespread pursuit of creative expression.

In seeking the origin of these developments, both common and sacred, researchers have invoked a wide range of explanations. For us, an essential guiding light will continue to be Darwinian evolution, applied now to human behavior. The brain, after all, is but another biological structure evolving via selection pressures, and it is the brain that informs what we do and how we respond. Over the past few decades, cognitive scientists and evolutionary psychologists have developed this perspective, establishing that much as our biology has been shaped by the forces of Darwinian selection, so too has our behavior. And thus in our trek across human culture we will often ask whether this or that behavior may have enhanced the prospects for survival and reproduction among those who long ago practiced it, promoting its wide propagation throughout generations of descendants. However, unlike the opposable thumb or upright gait—­inherited physiological features tightly linked to specific adaptive behaviors—­many of the brain’s inherited characteristics mold predilections rather than definitive actions. We are influenced by these predispositions but human activity emerges from a comingling of behavioral tendencies with our complex, deliberative, self-­reflective minds.

And so a second guiding light, distinct but no less important, will be trained on the inner life that comes hand in hand with our refined cognitive capacities. Following a trail marked by many thinkers, we will come to a revealing vista: with human cognition we surely harnessed a powerful force, one that in time elevated us to the dominant species worldwide. But the very mental faculties that allow us to shape and mold and innovate are the very ones that dispel the myopia that would otherwise keep us narrowly focused on the present. The ability to manipulate the environment thoughtfully provides the capacity to shift our vantage point, to hover above the timeline and contemplate what was and imagine what will be. However much we’d prefer it otherwise, to achieve “I think, therefore I am” is to run headlong into the rejoinder “I am, therefore I will die.”
© Elena Seibert
BRIAN GREENE is a professor of physics and mathematics and director of Columbia University's Center for Theoretical Physics and is renowned for his groundbreaking discoveries in superstring theory. He is the author of The Elegant UniverseThe Fabric of the Cosmos, and The Hidden Reality, which have collectively spent sixty-five weeks on The New York Times best-seller list and sold more than two million copies worldwide, and he has hosted two Peabody and Emmy Award winning NOVAminiseries based on his books. With producer Tracy Day, Greene cofounded the World Science Festival. He lives in New York. View titles by Brian Greene

About

NEW YORK TIMES BESTSELLER A captivating exploration of deep time and humanity's search for purpose, from the world-renowned physicist and best-selling author of The Elegant Universe.

"Few humans share Greene’s mastery of both the latest cosmological science and English prose." —The New York Times

Until the End of Time is Brian Greene's breathtaking new exploration of the cosmos and our quest to find meaning in the face of this vast expanse. Greene takes us on a journey from the big bang to the end of time, exploring how lasting structures formed, how life and mind emerged, and how we grapple with our existence through narrative, myth, religion, creative expression, science, the quest for truth, and a deep longing for the eternal. From particles to planets, consciousness to creativity, matter to meaning—Brian Greene allows us all to grasp and appreciate our fleeting but utterly exquisite moment in the cosmos.

Excerpt

1

The Lure of Eternity

Beginnings, Endings, and Beyond

In the fullness of time all that lives will die. For more than three billion years, as species simple and complex found their place in earth’s hierarchy, the scythe of death has cast a persistent shadow over the flowering of life. Diversity spread as life crawled from the oceans, strode on land, and took flight in the skies. But wait long enough and the ledger of birth and death, with entries more numerous than stars in the galaxy, will balance with dispassionate precision. The unfolding of any given life is beyond prediction. The final fate of any given life is a foregone conclusion.

And yet this looming end, as inevitable as the setting sun, is something only we humans seem to notice. Long before our arrival, the thunderous clap of storm clouds, the raging might of volcanoes, the tremulous shudders of a quaking earth surely sent scurrying everything with the power to scurry. But such flights are an instinctual reaction to a present danger. Most life lives in the moment, with fear born of immediate perception. It is only you and I and the rest of our lot that can reflect on the distant past, imagine the future, and grasp the darkness that awaits.

It’s terrifying. Not the kind of terror that makes us flinch or run for cover. Rather, it’s a foreboding that quietly lives within us, one we learn to tamp down, to accept, to make light of. But underneath the obscuring layers is the ever-­present, unsettling fact of what lies in store, knowledge that William James described as the “worm at the core of all our usual springs of delight.”1 To work and play, to yearn and strive, to long and love, all of it stitching us ever more tightly into the tapestry of the lives we share, and for it all then to be gone—­well, to paraphrase Steven Wright, it’s enough to scare you half to death. Twice.

Of course, most of us, in the service of sanity, don’t fixate on the end. We go about the world focused on worldly concerns. We accept the inevitable and direct our energies to other things. Yet the recognition that our time is finite is always with us, helping to shape the choices we make, the challenges we accept, the paths we follow. As cultural anthropologist Ernest Becker maintained, we are under a constant existential tension, pulled toward the sky by a consciousness that can soar to the heights of da Vinci, Shakespeare, Beethoven, and Einstein but tethered to earth by a physical form that will decay to dust. “Man is literally split in two: he has an awareness of his own splendid uniqueness in that he sticks out of nature with a towering majesty, and yet he goes back into the ground a few feet in order blindly and dumbly to rot and disappear forever.”2 According to Becker, we are impelled by such awareness to deny death the capacity to erase us. Some soothe the existential yearning through commitment to family, a team, a movement, a religion, a nation—­constructs that will outlast the individual’s allotted time on earth. Others leave behind creative expressions, artifacts that extend the duration of their presence symbolically. “We fly to Beauty,” said Emerson, “as an asylum from the terrors of finite nature.”3 Others still seek to vanquish death by winning or conquering, as if stature, power, and wealth command an immunity unavailable to the common mortal.

Across the millennia, one consequence has been a widespread fascination with all things, real or imagined, that touch on the timeless. From prophesies of an afterlife, to teachings of reincarnation, to entreaties of the windswept mandala, we have developed strategies to contend with knowledge of our impermanence and, often with hope, sometimes with resignation, to gesture toward eternity. What’s new in our age is the remarkable power of science to tell a lucid story not only of the past, back to the big bang, but also of the future. Eternity itself may forever lie beyond the reach of our equations, but our analyses have already revealed that the universe we have come to know is transitory. From planets to stars, solar systems to galaxies, black holes to swirling nebulae, nothing is everlasting. Indeed, as far as we can tell, not only is each individual life finite, but so too is life itself. Planet earth, which Carl Sagan described as a “mote of dust suspended on a sunbeam,” is an evanescent bloom in an exquisite cosmos that will ultimately be barren. Motes of dust, nearby or distant, dance on sunbeams for merely a moment.

Still, here on earth we have punctuated our moment with astonishing feats of insight, creativity, and ingenuity as each generation has built on the achievements of those who have gone before, seeking clarity on how it all came to be, pursuing coherence in where it is all going, and longing for an answer to why it all matters.

Such is the story of this book.

Stories of Nearly Everything

We are a species that delights in story. We look out on reality, we grasp patterns, and we join them into narratives that can captivate, inform, startle, amuse, and thrill. The plural—­narratives—­is utterly essential. In the library of human reflection, there is no single, unified volume that conveys ultimate understanding. Instead, we have written many nested stories that probe different domains of human inquiry and experience: stories, that is, that parse the patterns of reality using different grammars and vocabularies. Protons, neutrons, electrons, and nature’s other particles are essential for telling the reductionist story, analyzing the stuff of reality, from planets to Picasso, in terms of their microphysical constituents. Metabolism, replication, mutation, and adaptation are essential for telling the story of life’s emergence and development, analyzing the biochemical workings of remarkable molecules and the cells they govern. Neurons, information, thought, and awareness are essential for the story of mind—­and with that the narratives proliferate: myth to religion, literature to philosophy, art to music, telling of humankind’s struggle for survival, will to understand, urge for expression, and search for meaning.

These are all ongoing stories, developed by thinkers hailing from a great range of distinct disciplines. Understandably so. A saga that ranges from quarks to consciousness is a hefty chronicle. Still, the different stories are interlaced. Don Quixote speaks to humankind’s yearning for the heroic, told through the fragile Alonso Quijano, a character created in the imagination of Miguel de Cervantes, a living, breathing, thinking, sensing, feeling collection of bone, tissue, and cells that, during his lifetime, supported organic processes of energy transformation and waste excretion, which themselves relied on atomic and molecular movements honed by billions of years of evolution on a planet forged from the detritus of supernova explosions scattered throughout a realm of space emerging from the big bang. Yet to read Don Quixote’s travails is to gain an understanding of human nature that would remain opaque if embedded in a description of the movements of the knight-­errant’s molecules and atoms or conveyed through an elaboration of the neuronal processes crackling in Cervantes’s mind while writing the novel. Connected though they surely are, different stories, told with different languages and focused on different levels of reality, provide vastly different insights.

Perhaps one day we will be able to transit seamlessly between these stories, connecting all products of the human mind, real and fictive, scientific and imaginative. Perhaps we will one day invoke a unified theory of particulate ingredients to explain the overwhelming vision of a Rodin and the myriad responses The Burghers of Calais elicits from those who experience it. Maybe we will fully grasp how the seemingly mundane, a glint of light reflecting from a spinning dinner plate, can churn through the powerful mind of a Richard Feynman and compel him to rewrite the fundamental laws of physics. More ambitious still, perhaps one day we will understand the workings of mind and matter so completely that all will be laid bare, from black holes to Beethoven, from quantum weirdness to Walt Whitman. But even without having anything remotely near that capacity, there is much to be gained by immersion in these stories—­scientific, creative, imaginative—­appreciating when and how they emerged from earlier ones playing out on the cosmic timeline and tracing the developments, both controversial and conclusive, that elevated each to their place of explanatory prominence.4

Clear across the collection of stories, we will find two forces sharing the role of leading character. In chapter 2 we will meet the first: entropy. Although familiar to many through its association with disorder and the often-­quoted declaration that disorder is always on the rise, entropy has subtle qualities that allow physical systems to develop in a rich variety of ways, sometimes even appearing to swim against the entropic stream. We will see important examples of this in chapter 3, as particles in the aftermath of the big bang seemingly flout the drive to disorder as they evolve into organized structures like stars, galaxies, and planets—­and ultimately, into configurations of matter that surge with the current of life. Asking how that current switched on takes us to the second of our pervasive influences: evolution.

Although it is the prime mover behind the gradual transformations experienced by living systems, evolution by natural selection kicks in well before the first forms of life start competing. In chapter 4, we will encounter molecules battling molecules, struggles for survival waged in an arena of inanimate matter. Round upon round of molecular Darwinism, as such chemical combat is called, is what likely produced a series of ever more robust configurations ultimately yielding the first molecular collections we would recognize as life. The details are the stuff of cutting-­edge research, but with the last couple of decades of stupendous progress, the consensus is that we are heading down the right track. Indeed, it may be that the dual forces of entropy and evolution are well-­matched partners in the trek toward the emergence of life. While that might sound like an odd coupling—­entropy’s public rap veers close to chaos, seemingly the antithesis of evolution or of life—­recent mathematical analyses of entropy suggest that life, or at least lifelike qualities, might well be the expected product of a long-­lived source of energy, like the sun, relentlessly raining down heat and light on molecular ingredients that are competing for the limited resources available on a planet like earth.

Tentative though some of these ideas currently are, what’s certain is that a billion or so years after the earth formed it was teeming with life developing under evolutionary pressure, and so the next phase of developments is standard Darwinian fare. Chance events, like being hit by a cosmic ray or suffering a molecular mishap during the replication of DNA, result in random mutations, some with minimal impact on the organism’s health or welfare but others making it more or less fit in the competition for survival. Those mutations that enhance fitness are more likely to be passed on to descendants because the very meaning of “more fit” is that the trait’s carrier is more likely to survive to reproductive maturity and produce fit offspring. From generation to generation, qualities that enhanced fitness thus spread widely.

Billions of years later, as this long process continued to unfold, a particular suite of mutations provided some forms of life with an enhanced capacity for cognition. Some life not only became aware, but became aware of being aware. That is, some life acquired conscious self-­awareness. Such self-­reflective beings have naturally wondered what consciousness is and how it arose: How can a swirl of mindless matter think and feel? Various researchers, as we will discuss in chapter 5, anticipate a mechanistic explanation. They argue that we need to understand the brain—­its components, its functions, its connections—­with far greater fidelity than we now do, but once we have that knowledge, an explanation of consciousness will follow. Others anticipate that we are up against a far greater challenge, arguing that consciousness is the most difficult conundrum we have ever encountered, one that will require radically new perspectives regarding not just mind but also the very nature of reality.

Opinions converge when assessing the impact our cognitive sophistication has had on our behavioral repertoire. Across tens of thousands of generations during the Pleistocene, our forebears joined together in groups that subsisted through hunting and gathering. In time, an emerging mental dexterity provided them with refined capacities to plan and organize and communicate and teach and evaluate and judge and problem-solve. Leveraging these enhanced abilities of the individual, groups exerted increasingly influential communal forces. Which takes us to the next collection of explanatory episodes, those focused on developments that made us. In chapter 6 we examine our acquisition of language and subsequent obsession with the telling of stories; chapter 7 probes a particular genre of stories, those that foreshadow and transition into religious traditions; and in chapter 8 we explore the long-­standing and widespread pursuit of creative expression.

In seeking the origin of these developments, both common and sacred, researchers have invoked a wide range of explanations. For us, an essential guiding light will continue to be Darwinian evolution, applied now to human behavior. The brain, after all, is but another biological structure evolving via selection pressures, and it is the brain that informs what we do and how we respond. Over the past few decades, cognitive scientists and evolutionary psychologists have developed this perspective, establishing that much as our biology has been shaped by the forces of Darwinian selection, so too has our behavior. And thus in our trek across human culture we will often ask whether this or that behavior may have enhanced the prospects for survival and reproduction among those who long ago practiced it, promoting its wide propagation throughout generations of descendants. However, unlike the opposable thumb or upright gait—­inherited physiological features tightly linked to specific adaptive behaviors—­many of the brain’s inherited characteristics mold predilections rather than definitive actions. We are influenced by these predispositions but human activity emerges from a comingling of behavioral tendencies with our complex, deliberative, self-­reflective minds.

And so a second guiding light, distinct but no less important, will be trained on the inner life that comes hand in hand with our refined cognitive capacities. Following a trail marked by many thinkers, we will come to a revealing vista: with human cognition we surely harnessed a powerful force, one that in time elevated us to the dominant species worldwide. But the very mental faculties that allow us to shape and mold and innovate are the very ones that dispel the myopia that would otherwise keep us narrowly focused on the present. The ability to manipulate the environment thoughtfully provides the capacity to shift our vantage point, to hover above the timeline and contemplate what was and imagine what will be. However much we’d prefer it otherwise, to achieve “I think, therefore I am” is to run headlong into the rejoinder “I am, therefore I will die.”

Author

© Elena Seibert
BRIAN GREENE is a professor of physics and mathematics and director of Columbia University's Center for Theoretical Physics and is renowned for his groundbreaking discoveries in superstring theory. He is the author of The Elegant UniverseThe Fabric of the Cosmos, and The Hidden Reality, which have collectively spent sixty-five weeks on The New York Times best-seller list and sold more than two million copies worldwide, and he has hosted two Peabody and Emmy Award winning NOVAminiseries based on his books. With producer Tracy Day, Greene cofounded the World Science Festival. He lives in New York. View titles by Brian Greene