100 Best Life Sciences Books of All Time

Barack Obama

Former USA President

Fact or fiction, the president knows that reading keeps the mind sharp. He also delved into these non-fiction reads. [source]

Bill Gates

CEO/Microsoft

Both Melinda and I read this one, and it has sparked lots of great conversations at our dinner table. Harari takes on a daunting challenge: to tell the entire history of the human race in just 400 pages. He also writes about our species today and how artificial intelligence, genetic engineering, and other technologies will change us in the future. Although I found things to disagree with—especially Harari’s claim that humans were better off before we started farming—I would recommend Sapiens to anyone who’s interested in the history and future of our species. [source]

Reid Hoffman

CEO/LinkedIn

A grand theory of humanity. [source]

Charles T. Munger

Vice Chairman/Berkshire Hathaway

recommends this book in the second edition of Poor Charlie’s Almanack. [source]

Matt Ridley

Turned evolutionary biology on its head and was written like a great detective story. [source]

Phil Libin

CEO/Evernote

Had a profound influence on me pretty early on. [source]

Barack Obama

Former USA President

A few months ago, Mr. Obama read “Thinking, Fast and Slow,” by Daniel Kahneman, about how people make decisions — quick, instinctive thinking versus slower, contemplative deliberation. For Mr. Obama, a deliberator in an instinctive business, this may be as instructive as any political science text. [source]

Bill Gates

CEO/Microsoft

On Bill Gates's reading list in 2012. [source]

Marc Andreessen

Co-Founder/Andreessen Horowitz

Captivating dive into human decision making, marred by inclusion of several/many? psychology studies that fail to replicate. Will stand as a cautionary tale? [source]

Bill Gates

CEO/Microsoft

Explains how neglecting sleep undercuts your creativity, problem solving, decision-making, learning, memory, heart health, brain health, mental health, emotional well-being, immune system, and even your life span. [source]

Brad Feld

Co-Founder/Foundry Group

Several friends, who know I both love to sleep and am intrigued with how sleep works, recommended that I read Why We Sleep: Unlocking the Power of Sleep and Dreams. It was excellent. While my self-assessment of my sleep habits are very positive, I learned a few things. More importantly, I now have a much better understanding of the “Why” surrounding sleep, especially around sleep’s importance to a healthy and long life. [source]

Alexis Ohanian Sr.

Agree! Best book I've read this year. Wasted so many hours just proving to myself I'd be the last one up working at @reddit and for what??? Stupid. Diminishing marginal returns after enough hours without sleep. https://t.co/cT7fDNBF3A [source]

A.J. Jacobs

Great writer. [source]

Carl Zimmer

Yes. This is a fascinating book on so many different levels. It is really compelling as the story of the author trying to uncover the history of the woman from whom all these cells came. [source]

Bill Gates

CEO/Microsoft

"Mukherjee wrote this book for a lay audience, because he knows that the new genome technologies are at the cusp of affecting us all in profound ways," Gates wrote. Mukherjee is what Gates calls a "quadruple threat." He's a practicing physician, teacher, researcher, and author. [source]

Amit Paranjape

@vikramsathaye @DrSidMukherjee @kiranshaw Great book. [source]

Bryan Johnson

A great book. [source]

Bill Gates

CEO/Microsoft

I loved this brilliant book about cancer. [source]

Timothy J. Jorgensen

A tremendous amount of cancer biology comes through in that book through the eyes of the victims and the people up close and personal. [source]

Bill Gates

CEO/Microsoft

On Bill Gates's reading list in 2011. [source]

James Altucher

Founder/StockPickr

Gladwell is not the first person to come up with the 10,000 hour rule. Nor is he the first person to document what it takes to become the best in the world at something. But his stories are so great as he explains these deep concepts. How did the Beatles become the best? Why are professional hockey players born in January, February and March? And so on. [source]

Alex Circei

Question: What five books would you recommend to young people interested in your career path & why? Answer: Screw It, Let's Do It: Lessons In Life by Richard Branson Outliers: The Story of Success by Malcolm Gladwell Start With Why: How Great Leaders Inspire Everyone To Take Action by Simon Sinek The Hard Thing About Hard Things: Building a Business When There Are No Easy Answers by Ben Horowitz Rich Dad Poor Dad: What the Rich Teach Their Kids About Money That the Poor and Middle Class Do Not! by Robert T. Kiyosaki [source]

Amanda Palmer

Amanda Palmer recommended this book in the book "Tools of Titans". [source]

David Goldberg

What I really liked about A Short History of Nearly Everything is that it gives an excellent account of a lot of the personalities and the interconnectedness of important discoveries in cosmology and elsewhere. He does such a great job of bringing together our understanding of cosmology, evolution, paleontology, and geology in a very, very fluid way. [source]

Fabrice Grinda

I have lots of books to recommend, but they are not related to my career path. The only one that is remotely related is Peter Thiel’s Zero to One. That said here are books I would recommend. [source]

Bill Gates

CEO/Microsoft

Harari’s new book is as challenging and readable as Sapiens. Rather than looking back, as Sapiens does, it looks to the future. I don’t agree with everything the author has to say, but he has written a thoughtful look at what may be in store for humanity. [source]

Richard Branson

Founder/Virgin Group

I certainly wouldn’t consider myself a big reader of paleontology or anthropology – not good words for us dyslexics! – but I enjoy learning about how society has unfolded and history has developed in an exciting, easy to read way. The sequel, Homo Deus: A Brief History of Tomorrow, is a fascinating look into the future too. While these aren’t traditional business or leadership books, they are all about people – and learning how to work with, live with, interact with people and get the best out of them is what leadership is all about. [source]

Vinod Khosla

Co-Founder/Sun Microsystem

Not that I agree with all of it, but it is still mind-bending speculation about our future as a follow-up to a previous favorite, Sapiens. It’s directionally right. [source]

Barack Obama

Former USA President

President Obama is spending his Hawaiian vacation playing golf, getting together with high school friends and reading a handful of dark novels set in foreign lands, according to a book list released by the White House Wednesday. The presidential reading list includes … two works of non-fiction for the trip: … "Being Mortal: Medicine and What Matters in the End" by Dr. Atul Gawande. [source]

Malcolm Gladwell

Writer & Journalist

American medicine, Being Mortal reminds us, has prepared itself for life but not for death. This is Atul Gawande's most powerful--and moving--book. [source]

Indra Nooyi

Board of Directors/Amazon

Just finished "Being Mortal" by Atul Gawande. A beautifully written book. Captivating. [source]

Oliver Sacks Fdn.

As a writer, Oliver Sacks found gardens essential to the creative process. Check out our year-end newsletter, devoted to some beautiful books by botanist-writers that would make great gifts for all your plant-loving friends. https://t.co/2U8iEv4L1x https://t.co/IK1cgIMJhE [source]

Sarah Taber

Yeah that's because most of those books are actually just sanctimonious classists pretending they're trying to fix problems. That's why they're depressing If you want a book that's actually about moving forward, "Braiding Sweetgrass" is FANTASTIC. https://t.co/Drr1tmwhSs [source]

Bradley Voytek

I can’t imagine one day waking up and not knowing who my wife is, or seeing my wife and thinking that she was replaced by some sort of clone or robot. But that could happen to any of us. [source]

Suzanne O'Sullivan

I didn’t choose neurology because of it but the way Oliver Sacks writes about neurology is very compelling. [source]

Tanya Byron

This is a seminal book that anyone who wants to work in mental health should read. It is a charming and gentle and also an honest exposé of what can happen to us when our mental health is compromised for whatever reason. [source]

Barack Obama

Former USA President

The president also released a list of his summer favorites back in 2015: All That Is, James Salter The Sixth Extinction, Elizabeth Kolbert The Lowland, Jhumpa Lahiri Between the World and Me, Ta-Nehisi Coates Washington: A Life, Ron Chernow All the Light We Cannot See, Anthony Doerr [source]

Bill Gates

CEO/Microsoft

The Sixth Extinction: An Unnatural History, by Elizabeth Kolbert. Climate change is a big problem—one of the biggest we’ll face this century—but it’s not the only environmental concern on the horizon. Humans are putting down massive amounts of pavement, moving species around the planet, over-fishing and acidifying the oceans, changing the chemical composition of rivers, and more. Natural scientists posit that there have been five extinction events in the Earth’s history (think of the asteroid that wiped out the dinosaurs), and Kolbert makes a compelling case that human activity is leading to the sixth. Unlike a lot of people who write about the environment, Kolbert doesn’t resort to hype. She just lays out the facts and wraps them in memorable anecdotes. It’s a sobering but engaging and informative read. [source]

Jeff Bezos

Founder/Amazon

"In his autobiography, Walmart's founder expounds on the principles of discount retailing and discusses his core values of frugality and a bias for action — a willingness to try a lot of things and make many mistakes. Bezos included both in Amazon's corporate values," Brad Stone writes. [source]

Bill Gates

CEO/Microsoft

I don’t know how Kalanithi found the physical strength to write this book while he was so debilitated by the disease and then potent chemotherapy. But I’m so glad he did. He spent his whole brief life searching for meaning in one way or another -- through books, writing, medicine, surgery, and science. I’m grateful that, by reading this book, I got to witness a small part of that journey. I just wish the journey hadn’t been cut so short [source]

Ryan Holiday

Author

Despite its popularity, When Breath Becomes Air is actually underrated. It’s make-you-cry good. [source]

Bethany S. Mandel

More Shabbat reading recommendations: This book was breathtaking and such a powerful advertisement for the joy of parenthood. https://t.co/V8BH97eiL9 [source]

Barry Estabrook

Michael Pollan looks at food production through four meals. One is a fast-food meal, the other is an industrial-scale organic meal, then there is a small-scale organic meal and finally he actually goes out and either grows or kills, in the case of the meat, the entire meal himself. That is the narrative. [source]

Gabriel Coarna

Michael Pollan's "The Omnivore's Dilemma" --more precisely, the first 3rd of it-- was what first made me realize how badly the Earth, as an ecosystem, is out of balance. [source]

Paul Rozin

Michael Pollan is an excellent journalist who specializes in the food domain.He proposes relying more on whole foods and less on processed foods, like Oreo Cookies. He argues that unprocessed foods are more nutritious, more wholistic and better for the environment. [source]

Carol Dweck

For me it was exciting to read this book because while my research shows a growth mindset is really good for you, this book shows that a growth mindset also has a strong basis in modern neuroscience. It illustrates, though fascinating case histories and descriptions of recent research, the amazing power of the brain to change and even to reorganise itself with practice and experience. [source]

Bogdana Butnar

I don't have favourite books. I equate a favourite something with wanting to do it over and over again and I've never wanted to read a book too many times. I have favourite authors and I have books that changed me in significant ways because they moved me or taught me something or changed my view of the world. So, here's some of those books... [source]

Naveen Jain

I think the book that I really, really enjoy was, "The Brain That Changes Itself." It's all about neuroplasticity, you'd really love that book. [source]

Vinod Khosla

Co-Founder/Sun Microsystem

Reveals incredible scientific breakthroughs about aging and ways we can slow down, or even reverse, the process. [source]

Vinod Khosla

Co-Founder/Sun Microsystem

Reveals incredible scientific breakthroughs about aging and ways we can slow down, or even reverse, the process. [source]

Dave Asprey

Prepare to have your mind blown. You are holding in your hands the precious results of decades of work, as shared by Dr. David Sinclair, the rock star of aging and human longevity. [source]

Antonio Eram

This book was recommended by Antonio when asked for titles he would recommend to young people interested in his career path. [source]

Susan Jacoby

Richard Dawkins is very funny. One of the reasons for reading The God Delusion is that it will disabuse you of the idea – which is a common stereotype of atheists – that they are utterly humourless. You hear this over and over again. I’m often invited to college campuses to give lectures, and often they’re religious schools – not fundamentalist schools, but colleges of a historically religious type. And very often I will hear: “Oh I expected you to be small and dark-haired and wear glasses!” The image of the atheist woman is kind of like what the image of the feminist used to be, someone too ugly to get a man. But part of it is also humorlessness. People will often say to me, “Oh you’re so funny.” “Well, yeah!” [source]

Vote Dem For The Planet

@KimBledsoe14 @Goodbye_Jesus @Ian313f There were a lot of rebels and drifters in those days against the repressive regime. They had followers. Have you read “The God Delusion”? Great book. [source]

Sam Harris

I highly recommend. It really is the most accessible discussion of brain science you will find. [source]

Vinod Khosla

Co-Founder/Sun Microsystem

Among the best insights into our brain and behavior. A top of the charts for me for this year, along with Scale. [source]

Bryan Johnson

Bryan Johnson recommended this book on Twitter. [source]

Antonio Eram

This book was recommended by Antonio when asked for titles he would recommend to young people interested in his career path. [source]

Mark O'Connell

I wouldn’t be the first to look at him this way but I read Kurzweil’s work as essentially a work of religious mysticism. I think there’s no other way to read it, really. [source]

Steve Aoki

It opened me up to the idea of science fiction becoming science fact. [source]

Chelsea Frank

I read everything with an open mind, often challenging myself by choosing books with an odd perspective or religious/spiritual views. These books do not reflect my personal feelings but are books that helped shape my perspective on life, love, and happiness. [source]

David Brooks

He argues that most of our moral decisions are that kind of an instant reaction. It’s like aesthetics: when we see a scene we know instantly if it’s beautiful or not. [source]

Emrys Westacott

Haidt has a formula for happiness: Genetics + conditions + choices. This is a formula for a realistic approach to trying to achieve the good life. [source]

Neil deGrasse Tyson

Astrophysicist, Author & Science Communicator

Which books should be read by every single intelligent person on planet? … On the Origin of Species (Darwin) to learn of our kinship with all other life on Earth. If you read all of the above works you will glean profound insight into most of what has driven the history of the western world. [source]

Mark Kurlansky

It is one of the most important books written, and I always urge people to read it. [source]

Adam Maloof

For me (and many others) this book forms the foundation for modern biology. It is all about humans’ concept of themselves. [source]

Timothy Ferriss

Author & Entrepreneur

I agree wholeheartedly with a lot of the co-opted science, which people can read a book called Bad Science, which is by a doctor named Ben Goldacre. It’s great. [source]

Bryan Callen

Great book, yeah. [source]

Charles Poliquin

You would stop making those dumb comments if you read this book. [source]

Lilian Ong

I gained clarity and a different perspective of living a life with purpose. I learned that how we are “wired” or our S.H.A.P.E can help us find the purpose of our life. [source]

Robert Katai

I have 2 books that resonate with me and my work. The first one is a book written by Rick Warren called “The Purpose-Driven Life” and the second one is “Purple Cow” by Seth Godin. These are the books that I can read over and over again, because they always remind me what’s my purpose in this life, in my daily job and what I can do with my projects and work to create a purple cow effect. [source]

Theresa Evanoff

Here are some of my favourites around purpose, positive habits, positive thinking, and business goals. I’m a firm believer that subject expertise can be learned, but character-building traits, like perseverance and purposefulness, must be honed. “Purpose Driven Life”, Rick Warren “Start with Why” by Simon Sinek “The 7 Habits of Highly Effective People”, Stephen Covey "The Magic of Thinking Big", David J. Schwartz "The Power of Positive Thinking" by Norman Vincent Peale "The Hard Thing About Hard Things" by Ben Horowitz “Good to Great”, Jim Collins “Doing Good Well”, Willie Cheng [source]

Bill Gates

CEO/Microsoft

On Bill Gates's reading list in 2012. [source]

Jeff Bezos

Founder/Amazon

From the book "The Everything Store: and the Age of Amazon" “The scholar argues that people are wired to see patterns in chaos while remaining blind to unpredictable events, with massive consequences. Experimentation and empiricism trumps the easy and obvious narrative,” Stone writes. [source]

James Altucher

Founder/StockPickr

And throw in “The Black Swan” and “Fooled by Randomness”. “Fragile” means if you hit something might break. “Resilient” means if you hit something, it will stay the same. On my podcast Nassim discusses “Antifragility” – building a system, even on that works for you on a personal level, where you if you harm your self in some way it becomes stronger. That podcast changed my life He discusses Antifragility throughout history, up to our current economic situation, and even in our personal situations. [source]

Bill Gates

CEO/Microsoft

Of the five books I finished over vacation, the one that impressed me the most – and that is probably of broadest interest – is Moonwalking with Einstein: The Art and Science of Remembering Everything, by science writer Joshua Foer. This is an absolutely phenomenal book that looks at memory and techniques for dramatically improving memory. Foer actually mastered these techniques, which led him to the finals of the U.S. Memory Championship. His book gives fascinating insights into how the mind works. [source]

Chelsea Handler

It has changed my life and made me embarrass myself much less when meeting someone twice. [source]

Deborah Blum

This book focuses not so much on the scientists but more on the consequence and meaning of memory for the rest of us. Within the framework of a memory championship, Foer looks at this almost obsessive interest in learning, how to remember everything. He asks the really interesting philosophical question, which is, are we defined by what we remember? [source]

Barack Obama

Former USA President

As 2018 draws to a close, I’m continuing a favorite tradition of mine and sharing my year-end lists. It gives me a moment to pause and reflect on the year through the books I found most thought-provoking, inspiring, or just plain loved. It also gives me a chance to highlight talented authors – some who are household names and others who you may not have heard of before. Here’s my best of 2018 list. [source]

Bill Gates

CEO/Microsoft

Anyone who wants to discuss how artificial intelligence is shaping the world should read this book. [source]

Elon Musk

Founder/SpaceX

A compelling guide to the challenges and choices in our quest for a great future of life, intelligence and consciousness—on Earth and beyond. [source]

Jon Najarian

I believe both the corona virus and ebola have a bat connection. Scary, but great book on ebola: Hot Zone by Richard Preston https://t.co/jGEjbrB7pZ [source]

Pierre Haski

@ChuBailiang The hot zone, it made my days during SARS in Beijing, a great book! https://t.co/8E8AYgIhp7 [source]

Kirk Borne

As #AI moves toward #AGI with #NeuralNetworks, deeper understanding of Emotion Science is critical! See "How Emotions Are Made — The Secret Life of the Brain" by @LFeldmanBarrett Get the book: https://t.co/MH4f0mgnrs Watch her amazing video on @TEDTalks https://t.co/hPFB1vx4me https://t.co/hzZ4z2RCIr [source]

Margaret Morris

I appreciate Lisa Feldman Barrett’s argument that we can become the architects of our experiences. She pushes against the idea that events trigger emotions in a predetermined way and suggests we find the most specific language possible to describe our experiences and feelings. This specificity may propel us to move forward from challenges in a constructive way. [source]

Robert Cialdini

Author

Dobelli examines our most common decision-making failings with engaging eloquence and describes how to counter them with instructive good sense. [source]

Nigel Warburton

This is an unpretentious book. Dobelli doesn’t claim to be an original thinker himself. He’s a summariser of other people’s thoughts. What he’s done is brought lots of different things together in one place. Each of the 99 entries is pretty short, and it’s the kind of book to dip into. [source]

Mark Zuckerberg

Founder/Facebook

This book aims to tell a history of humanity from the perspective of genetics rather than sociology. This should complement the other broad histories I've read this year, as well as follow "Energy" well in focusing on science. I've wanted to read Matt Ridley's books for a while. His recent book "The Rational Optimist" about how progress and the economy evolve is also near the top of my ever-growing pile of books to read. [source]

Naval Ravikant

CEO & Co-Founder/AngelList

Getting into the more evolution, science kind of books, I really highly, highly recommend picking up Genome … . [source]

James Randi

They talk about the blind watchmaker not being able to make a watch, but if you’re given an almost infinite number of combinations and permutations of materials and situations, the world will come about. Or it may not. In our case, it came about. You’re here, I’m here, and I’m very happy about that. [source]

Jerry Coyne

If I had to pick just one self-contained book that lays out Dawkins’s philosophy and methodology, and shows his literary skills, I would have to pick this one. [source]

Kenneth Miller

In the Dawkins book I chose, The Blind Watchmaker, he brilliantly explains how complex mechanisms and structures are put together by the process of evolution. It is true that he makes certain theological points that I don’t agree with. [source]

Carl Zimmer

Even when living things are operating normally and humming along, it’s still beyond our ordinary understanding. You really have to stretch your powers of imagination to try to get a sense of what it is like inside of a cell. Ironically, textbooks can make that imagination more difficult. If they want to show how genes are used to make proteins, they show a very tiny, isolated piece of DNA, and then an isolated strand of RNA, and an isolated ribosome that uses the RNA to make a protein – as if that was all there was in the cell. But the fact is that every cell is actually crammed with molecules, all of which have really important things to do. [source]

Stephen Curry

@cshperspectives @MHendr1cks David Goodsell’s book, The Machinery of Life, is great for showing molecular crowding. https://t.co/s7h7Yx2MIk [source]

Isabella Tree

Quammen’s wondrous peregrination of islands takes us on a journey of evolutions and extinctions in order to illustrate how like islands our continents have become. [source]

Sean B Carroll

The book covers the role that islands have played in our thinking about how nature works. [source]

TC Boyle

A brilliant journalist who can tell scientific stories with the kind of panache you’d expect from a novelist. [source]

Carl Zimmer

I chose this because I think it expresses a really important idea. Richard Dawkins wrote this book not long after The Selfish Gene came out. That was his landmark book, in which he argued for a gene-centric view of evolution. Genes build bodies. They build traits, which are known as phenotypes, in order to be replicated in the next generation. [source]

Peter Atkins

Shows a highly imaginative approach to understanding the nature of the biosphere. A very clever book. [source]

Peter Attia

Founder/Attia Medical

One of the books that considers to be an important read for people interested in his career path. [source]

Matt Ridley

An astonishing literary achievement, and it was about the greatest scientific discovery of the 20th century. [source]

Adam Hart-Davis

They made a brilliant guess and the result was that they and Maurice Wilkins shared a Nobel Prize and Rosalind Franklin didn’t, which was very unfair. [source]

Beth Shapiro

He describes in this book not only the beauty of these animals, but the human landscape they live in and what a disastrous time he has getting to these locations. [source]

Gaia Vince

This is a book obviously for readers but it’s also a book for writers of science to understand how to capture the imagination of readers. [source]

Mark Lynas

For me, Last Chance to See is a real eye-opener, with the idea that you can take a depressing subject – species on the verge of extinction – and present it in a way which is so engaging, so funny and so humane. [source]

Antonio Eram

This book was recommended by , Founder of NETOPIA mobilPay, when asked for titles he would recommend to people interested in understanding the world around them. [source]

Dave Collum

I guess it is a good time to point out that "The Great Influenza" is a great book. If you think modern medicine would have mitigate this one, you haven't read the book. https://t.co/t4uHPgfLE6 [source]

Greg Dworkin

@heshsson yes1 brilliant book, which also explains flu better than most other things you will read [source]

Adam Conover

@TheBaltimoreSon @CharlesCMann Sure it! A total revolution in my understanding of history, all in one book. Amazing stuff. [source]

Colin Calloway

The book provides a huge hemispheric overview. [source]

Scott Keyes

It’s one of those books that takes everything you thought you knew about the history of European colonialists and indigenous groups in the Americas and turns it on its head. Just a fascinating deep-dive into early American history that questions a lot of dogma we were taught in school. [source]

Aniela Gregorek

I gained a deeper understanding of how music affects our moods and our brains. [source]

Justin Boreta

Justin Boreta said this is one of his most-recommended books. [source]

John Gray

Civilisation, as Freud understands it, begins with the restraint of violence… which means that the civilisational condition is one of discontent. [source]

David Bell

A dispassionate view of the cost of civilisation to the individual. [source]

Sam Freedman

A rough synopsis of the book is that love is a social construct designed to prevent us from murdering each other, at the expense of creating profound neurosis, so definitely a bold choice for a second date. https://t.co/pEnlgR6aiL [source]

Marvin Liao

Partner/500 Startups

I tend to jump from book to book and may switch if I am interested in some new topic. This is a pleasure for me (which I also do benefit work wise from too). It’s quite a random list because I have eclectic interests (or just scatterbrained most likely) on tech business, AI, general global economy, geopolitics, rising Biotech economy & history. I'm basically 15% to 50% into all these books. [source]

Linda Xie

Really enjoyed the book "A Crack in Creation" co-authored by Jennifer Doudna, one of the scientists who discovered CRISPR. It goes over the history of gene editing, how it works (gets pretty technical), fascinating experiments, and future implications https://t.co/lM36xJ1BLL [source]

Robin Sharma

I think you’ll gain great value—and reading joy—from this book. Have an excellent Saturday. Love, Robin https://t.co/8e5D4Y2LLp [source]

Roxana Bitoleanu

One of the books recommends to young people interested in her career path. [source]

Adam Maloof

This book looks at a classic Carl Sagan idea that if there are zillions of stars and bazillions of planets in the universe, then there must be at least millions of habitable planets with complex life. [source]

James Kasting

They are very pessimistic about the chances of complex life outside Earth, by which they mean animal life, and, of course, that includes intelligent life. [source]