Tell us a bit about Sum.

Sum is a work of literary fiction composed of forty mutually exclusive stories. Each story offers a different reason for our existence and the meaning of life and death. These are not serious proposals; they’re satirical and thought provoking lenses through which to see our lives at new angles.

Can you give us some examples?

In different stories, God is a married couple, God is a committee, God is a species of dimwitted creatures, or God is the size of a bacterium. In other stories there is no God at all and people in the afterlife battle over stories of His non-existence. In other stories we are mobile rovers built by planetary cartographers, or we are ten-dimensional creatures taking a vacation in three-dimensional bodies, or our life runs backwards after the expansion of the universe reverses and you get to see all the details you mis-remembered.

How long did it take you to write Sum?

Seven years. I wrote over 75 stories, but only included those in the book that created the right combination.

Tell us about the title.

I chose Sum for three reasons. First, it’s Latin for ‘I am’, as in cogito ergo sum. Second, it’s related to the Latin term for the highest, as in summa cum laude, or the English word summit. Third, the point of this book is that the whole is greater than the sum of the parts. As you read the stories, it becomes clear that they are mutually exclusive and that there’s something bigger emerging from adding them all together.

What is that something bigger?

It’s the appreciation that there are a lot of possibilities available for what’s going on out there. I’m often surprised by the number of people who seem to have total certainty about the religious stories they were raised on. They have no doubt about the absolute truth of their story, even though every other adherent in every other religion shares that same certainty and knows that all other religions are patently untrue. I’m dismayed at how little we explore the giant number of other possibilities. There are ideas far beyond the things you’ll find in anyone’s bible, and there’s too little dialog about this. So I don’t think the important thing should be to commit to a particular story when there’s no evidence supporting any one over the others. The important thing should be to explore and celebrate the vast possibilities. The mutual exclusivity of the stories in Sum are designed to allow this. The aim of this book is to swing a flashlight around the possibility space.

So do you believe any of the stories in Sum could be true?

None are meant to be serious proposals. The only serious proposal is the emergent message of the book: that there are many possibilities, and we should be discussing the size of that space instead of battling over the details of the pitifully few stories that our ancestors entertained.

But do you consider any of the stories in Sum more probable than any others?

They are all equally improbable.

Do you believe in anything?

I believe in possibility.

Is that compatible with your scientific career?

It is the heart of a scientific career. Real science always operates by holding lots of interesting possibilities in mind and working to see which one is most supported by the data. Sometimes it’s difficult or impossible to gather data that weighs in–and in those cases you simply hold the possibilities. You don’t commit to a particular version of the story when there is no reason to privilege one over the others.

But as a scientist, do you think we may be able to someday answer these questions about life’s meaning?

Yes, maybe someday. I am not a mysterian, who believes that science will never be able to shed light on the deep questions. But I certainly don’t think we’ll answer these in my brief twinkling of a 21st century lifetime. I’ve devoted my life so far to scientific pursuit, because if you want to figure out what’s going on this world, there is no better way than to directly study the blueprints. And science over the past 400 years has been tremendously successful. We reached the moon and eradicated smallpox and built the Net and tripled life spans–and we’ve increasingly tapped into those mind-blowing blueprints, and they’re deeper and more beautiful than anyone could have guessed. But in the end, when you reach the end of the pier of everything we know in science, you find that it has taken us only part way, and beyond that all you see is uncharted water. Beyond the end of the pier lies all the rest, all the mystery about our deeply strange existence. The equivalence of mass and energy, dark matter, multiple spatial dimensions, how to build consciousness from pieces and parts, what live and death are about, and so on. I have no doubt that we will continue to build the pier out, several new slats in each generation, but we have no guarantee how far we’ll get. And that ocean is pretty big. There may be some domains that are beyond the tools of science–perhaps temporarily, perhaps always.

Does your book belong to the group of recent books by the “new athiests”?

I don’t really see it that way. The recent books by Dawkins, Dennett, Harris, Hitchens and others are brilliant and insightful, but they also feed a common misconception that scientists don’t have the capacity to gambol around beyond the available data. The truth is that good scientists are among the most open-minded people. Science is nothing but careful thinking, and careful thinking encourages an appreciation of the complexity of the world, and this complexity encourages us to maintain several possibilities in our head at once. In a single lifetime, we may have no way to disambiguate these possibilities. And that’s okay. A scientist may tend to favor one story over the others, but will always be careful to concede uncertainty and maintain a willingness to change the balance with new, incoming information. As an example, there are two very different interpretations about the reality underlying quantum physics. It is possible that there will be no way to ever know which is correct, or if instead some entirely new theory is correct. And that ambiguity is accepted as part of the enormity of the mysteries we face. Those are often the terms of the agreement we have with Mother Nature.

Are you personally an atheist?

It depends what you mean by that. As a teenager I was an atheist. I realize now that my drive to talk with people about atheism was nothing more than a desire to get them to admit that something else could be possible other than the view that they absorbed from their parents or their community or their culture. It is not difficult to recognize that if you’re born in Saudi Arabia, your nervous system is likely to absorb a belief in Islam; if you’re born in India, you love Hinduism; most Americans soak up Christianity, and so on. Brains in different locations are exposed to different contexts, and they come to believe the local stories with equal passion and fervor. After childhood indoctrination people will vigorously defend their story against all the other stories, which seem to them fundamentally ridiculous. For many people, this connection to the numinous is an important part of their lives. But to be members of a larger community, I think it’s an important exercise to stretch ourselves mentally to consider all the things we do not really know.

Do you think some form of religion is possible?

I think most scientists are, in some sense, religious. But not in the traditional way. As the philosophers Russell and Whitehead pointed out, spiritual impulses should be built upon the bedrock of what we already know. We know quite a bit about the size of the cosmos at this point, and quite a bit about the biological algorithms in our bodies, and the strange quantum behavior of atoms, and so on. So the idea is to use this knowledge as a springboard for any reasonable religion, instead of books written millennia ago by people who never had the opportunity to know about DNA, extra-solar planets, bacterial infection, information theory, electricity, the Big Bang and Big Crunch, or even other cultures or literatures or landscapes. Many traditional stories are beautiful, and they often crystallize hard-won wisdom. But in my opinion, the traditional religions are likely to be too small-thinking to possibly be correct. We know so much more now. So, yes, I think it’s possible and even desirable to have a deep awe for the mysteries around us, and one can call this a form of religion.

So would you call yourself an agnostic?

No. As it is commonly used, I find the term agnostic weak. It is usually used to mean “I’m not really certain whether the guy with the long beard on the clouds exists or does not exist.”  But there are more exciting directions to pursue–namely, seeking entirely new frameworks we haven’t yet considered.

Do you call yourself anything?

I call myself a Possibilian.

"What Eagleman seems to be calling for is a new Enlightenment."
- Sunday Herald
"A popularizer of impressive gusto...[Eagleman] aims, grandly, to do for the study of the mind what Copernicus did for the study of the stars."
- New York Observer
"[A] neuroscientist and polymath."
- Wall Street Journal
"David Eagleman offers startling lessons.... His method in both Sum and his new book, Incognito, is to ask us to cast off our lazy, commonplace assumptions."
- The Guardian
"Eagleman has a talent for testing the untestable, for taking seemingly sophomoric notions and using them to nail down the slippery stuff of consciousness."
- The New Yorker
"David Eagleman may be the best combination of scientist and fiction-writer alive."
- Stewart Brand
"David Eagleman is the kind of guy who really does make being a neuroscientist look like fun."
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