What are the chances of your coming into being?


A little while ago I had the privilege of attending TEDx San Francisco, organized by the incomparable Christine Mason McCaull.  One of the talks was by Mel Robbins, a riotously funny self-help author and life coach with a syndicated radio show.  In it, she mentioned that scientists calculate the probability of your existing as you, today, at about one in 400 trillion (4×1014).

“That’s a pretty big number,” I thought to myself.  If I had 400 trillion pennies to my name, I could probably retire.

Previously, I had heard the Buddhist version of the probability of ‘this precious incarnation’.  Imagine there was one life preserver thrown somewhere in some ocean and there is exactly one turtle in all of these oceans, swimming underwater somewhere.  The probability that you came about and exist today is the same as that turtle sticking its head out of the water — in the middle of that life preserver.  On one try.

So I got curious: are either of these numbers correct?  Which one’s bigger?  Are they gross exaggerations?  Or is it possible that they underestimate the true number?

First, let us figure out the probability of one turtle sticking its head out of the one life preserver we toss out somewhere in the ocean.  That’s a pretty straightforward calculation.

According to WolframAlpha, the total area of oceans in the world is 3.409×108 square kilometers, or 340,900,000 km2 (131.6 million square miles, for those benighted souls who still cling to user-hostile British measures).  Let’s say a life preserver’s hole is about 80cm in diameter, which would make the area inside

3.14(0.4)2=0.5024 m2

which we will conveniently round to 0.5 square meters.  If one square kilometer is a million square meters, then the probability of Mr Turtle sticking his head out of that life preserver is simply the area inside the life preserver divided by the total area of all oceans, or

0.5m2/3.409×108x106m2 = 1.47 x 10-15

or one in 6.82×1014, or about 1 in 700 trillion.

One in 400 trillion vs one in 700 trillion?  I gotta say, the two numbers are pretty darn close, for such a farfetched notion from two completely different sources: old-time Buddhist scholars and present-day scientists.  They agree to within a factor of two!

So to the second question: how accurate is this number?  What would we come up with ourselves starting with first principles, making some reasonable assumptions and putting them all together?  That is, instead of making one big hand-waving gesture and pronouncing, “The answer is five hundred bazillion squintillion,” we make a series of sequentially-reasoned, smaller hand-waving gestures so as to make it all seem scientific. (This is also known as ‘consulting’ – especially if you show it all in a PowerPoint deck.)

Oh, this is going to be fun.

First, let’s talk about the probability of your parents meeting.  If they met one new person of the opposite sex every day from age 15 to 40, that would be about 10,000 people.  Let’s confine the pool of possible people they could meet to 1/10 of the world’s population twenty years go (one tenth of 4 billion = 400 million) so it considers not just the population of the US but that of the places they could have visited.  Half of those people, or 200 million, will be of the opposite sex.  So let’s say the probability of your parents meeting, ever, is 10,000 divided by 200 million:

104/2×108= 2×10-4, or one in 20,000.

Probability of boy meeting girl: 1 in 20,000.

So far, so unlikely.

Now let’s say the chances of them actually talking to one another is one in 10.  And the chances of that turning into another meeting is about one in 10 also.  And the chances of that turning into a long-term relationship is also one in 10.  And the chances of that lasting long enough to result in offspring is one in 2.  So the probability of your parents’ chance meeting resulting in kids is about 1 in 2000.

Probability of same boy knocking up same girl: 1 in 2000.

So the combined probability is already around 1 in 40 million — long but not insurmountable odds.  Now things start getting interesting.  Why?  Because we’re about to deal with eggs and sperm, which come in large numbers.

Each sperm and each egg is genetically unique because of the process of meiosis; you are the result of the fusion of one particular egg with one particular sperm.  A fertile woman has 100,000 viable eggs on average.  A man will produce about 12 trillion sperm over the course of his reproductive lifetime.  Let’s say a third of those (4 trillion) are relevant to our calculation, since the sperm created after your mom hits menopause don’t count.  So the probability of that one sperm with half your name on it hitting that one egg with the other half of your name on it is

1/(100,000)(4 trillion)= 1/(105)(4×1012)= 1 in 4 x 1017, or one in 400 quadrillion.

Probability of right sperm meeting right egg: 1 in 400 quadrillion.

But we’re just getting started.

Because the existence of you here now on planet earth presupposes another supremely unlikely and utterly undeniable chain of events.  Namely, that every one of your ancestors lived to reproductive age – going all the way back not just to the first Homo sapiens, first Homo erectus and Homo habilis, but all the way back to the first single-celled organism.  You are a representative of an unbroken lineage of life going back 4 billion years.

Let’s not get carried away here; we’ll just deal with the human lineage.  Say humans or humanoids have been around for about 3 million years, and that a generation is about 20 years.  That’s 150,000 generations.  Say that over the course of all human existence, the likelihood of any one human offspring to survive childhood and live to reproductive age and have at least one kid is 50:50 – 1 in 2.  Then what would be the chance of your particular lineage to have remained unbroken for 150,000 generations?

Well then, that would be one in 2150,000 , which is about 1 in 1045,000– a number so staggeringly large that my head hurts just writing it down. That number is not just larger than all of the particles in the universe – it’s larger than all the particles in the universe if each particle were itself a universe.

Probability of every one of your ancestors reproducing successfully: 1 in 1045,000

But let’s think about this some more.  Remember the sperm-meeting-egg argument for the creation of you, since each gamete is unique?  Well, the right sperm also had to meet the right egg to create your grandparents.  Otherwise they’d be different people, and so would their children, who would then have had children who were similar to you but not quite you.  This is also true of your grandparents’ parents, and their grandparents, and so on till the beginning of time.  If even once the wrong sperm met the wrong egg, you would not be sitting here noodling online reading fascinating articles like this one.  It would be your cousin Jethro, and you never really liked him anyway.

That means in every step of your lineage, the probability of the right sperm meeting the right egg such that the exact right ancestor would be created that would end up creating you is one in 1200 trillion, which we’ll round down to 1000 trillion, or one quadrillion.

So now we must account for that for 150,000 generations by raising 400 quadrillion to the 150,000th power:

[4×1017]150,000 ≈ 102,640,000

That’s a ten followed by 2,640,000 zeroes, which would fill 11 volumes of a book the size of The Tao of Dating with zeroes.

To get the final answer, technically we need to multiply that by the 1045,000 , 2000 and 20,000 up there, but those numbers are so shrimpy in comparison that it almost doesn’t matter.  For the sake of completeness:

(102,640,000)(1045,000)(2000)(20,000) = 4x 102,685,007 ≈ 102,685,000

Probability of your existing at all: 1 in 102,685,000

As a comparison, the number of atoms in the body of an average male (80kg, 175 lb) is 1027.  The number of atoms making up the earth is about 1050.  The number of atoms in the known universe is estimated at 1080.

So what’s the probability of your existing?  It’s the probability of 2 million people getting together – about the population of San Diego – each to play a game of dice with trillion-sided dice. They each roll the dice, and they all come up the exact same number – say, 550,343,279,001.

A miracle is an event so unlikely as to be almost impossible.  By that definition, I’ve just shown that you are a miracle.

Now go forth and feel and act like the miracle that you are.

Think about it,

Ali B

Thanks for visiting! You can find more of my writing here and here. I also wrote a book on how smart women can find more love, which turns out to be the highest-rated of its kind on Amazon (4.9/5 stars). The book on how smart men can be more successful with women is also alright.

PS: Update 9/26/11: To all you smartypants out there who just can’t wait to tell me “the probably of existing of something that exists is 100%” and “this is all just hand-waving” — yes, Einstein, I know, and you’re totally missing the point.  The probability of sentient life is not something that can be measured accurately, and hundreds of steps have been deleted for simplicity.  It’s all an exercise to get you thinking, but some of you are so damn smart and obsessed with being right that you’ve lost the mental capacity to wonder and instead harp on the numerical accuracy of the calculation.  And no matter how you slice it, it’s pretty remarkable that you and I, self-absorbed scallywags that we are, stand at the end of an unbroken chain of life going all the way back to the primordial slime.  That’s the point.  Now if you have something interesting to say, I’ll approve the comment, otherwise into the slag-heap of trolls it goes.

Update 11/10/11: Someone at imgur.com came up with this beautiful infographic, which apparently made the rounds of the planet while I was asleep.  Click on it to get the full-size version.


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  1. D

    September 24, 2011 @ 10:02 am


    great article man, enjoyed reading this one and the medicine one. You should really write more often.

  2. Joss

    September 25, 2011 @ 12:32 am


    This was amazing. Ditto above.

  3. Dwayne Litzenberger

    September 25, 2011 @ 12:42 am


    This kind of reasoning is so silly! What’s the probability that I exist? The probability that I exist, given the fact that I’m asking the question, is exactly 1.

  4. Vonskippy

    September 25, 2011 @ 1:31 am


    Did it hurt pulling all those numbers out of your ass?

    Without actual data, your assumptions are just that, assumptions.

    Like the Drake equation, people fill in the unknowns with whatever number will result in the equation fitting their current pet theory.

    You wanted a astronomical end result, so your numbers reflect that, except that casual evidence points out that people are no where near that unique.

    How many times have you traveled somewhere and just out of the blue met your doppelganger? Or looked across the stadium and saw a complete stranger that was the spitting image of your friend/wife/neighbor/famous person? Watched a movie/play and heard someone laugh exactly like your wife/friend/relative? How many identical patents, inventions, ideas, stories, songs, etc are created within seconds of each other by different people?

    Besides a limited number of physical combinations, personality/intellect/psyche are shaped (at least to some degree) by the environment. If humans didn’t follow a reasonably strict development path, they wouldn’t be humans.

    Just like it takes only 23 people to have a 50% probability of two of those people sharing a birthday, I think the number of unique human combinations possible that make “you” you, is probably way (way way way way way way) south of 1 in 10 to the 2,685,000 power.

    Right or wrong – interesting concept to mull over.

  5. Nimeton

    September 25, 2011 @ 2:55 am


    Throw a dice ten trillion times and wonder then why exactly this ten trillion long series of numbers 1-6 happened…

  6. fffff

    September 25, 2011 @ 3:08 am


    First place this falls apart: “Probability of boy meeting girl: 1 in 20,000.” The distribution of People, who they meet, and who they fall in love with is not random and uniform. Some outcomes are much likelier than others. The number of candidate mates is probably much smaller than this. This is even more the case historically, outside of cities, where it might easily have been in the dozens. (Remember, urbanization is new.) So taking your figure back times 150,000 generations is even wronger.

    But why do you stop after 150,000 generations, anyway? What’s the probability of the universe existing in a configuration which produces the planet Earth, life, and billions of years of evolution, hmm? What’s the probability of a universe existing that contains physics as we know it? When you get down to it, the probability of the universe is probably 0. (Unless all possibilities which are possibly possible are real in some universe, in which case the probability of anything that happens is clearly 1.)

    So the main handwavey point of “omfg miracle” is all well and good, but these numbers are fudgier than Willy Wonka. You should be ashamed of pretending you’re doing math. Consultant indeed.

  7. mer

    September 25, 2011 @ 3:54 am


    Great article,thanks man!

  8. John

    September 25, 2011 @ 4:18 am


    Very interesting article, full of positivism! When you are reminded how lucky you are just to be, it really fuels your desire to make the most of it. Thanks Ali!

  9. apa

    September 25, 2011 @ 4:20 am


    I read a similar quote a while ago in a religious debate, it started something like your post but ended with. “Probability that all the above happened, given that you already exist and are able to think about it: 100%” In other words the probability of your own existence can’t be used as a proof that life must have been created by some intelligent upper being.

  10. Sario

    September 25, 2011 @ 5:15 am


    You forgot to account for the mutations that might occur during meiosis. :P
    I looked around google a bit, but couldn’t find any probabilities for that. But they are important, as without these we would never have developed into the modern human at all.

  11. jimworm

    September 25, 2011 @ 5:31 am


    If you’re reading this, your probability of existing is 1. The probability of all known-to-have-happened to events to have happened is always 1.

    Of course, that assumes that the knowledge is correct; but even the most die-hard skeptic can be absolutely certain that they themselves exist.

  12. nana

    September 25, 2011 @ 6:55 am


    My head hurts,
    this unique, one of a kind miracle head.

    Thanks for doing this exercise.
    It makes one appreciate more that ‘being’ happens and this entity can perceive ‘being’.

  13. Josh Strike

    September 25, 2011 @ 7:20 am


    Good read. You missed a few things like, the probability of our planet being in a habitable zone around a star; the probability of that meteor wiping out the dinosaurs; and the fact that you wouldn’t be who you are now if you’d been born in, say, the Roman empire…or arguably even a day earlier or later than you were.

    Another question would be — given the number of random things that have happened since your birth, what are the odds that you sat at a computer and typed exactly this article? In that sense, there is an infinite subset of the infinite set, composed of possible versions of you.

    The takeaway from this is actually that you live in the only universe in which you can observe yourself as you are now…but there are also infinite subsets in which someone very similar to you is making the same lonely observation. When you look at it that way, it seems inevitable that you should arise to ask this question.

  14. Stephan Schubert

    September 25, 2011 @ 7:31 am


    Wow, a mind-blowing number/probability :)

  15. Sulcata

    September 25, 2011 @ 8:32 am


    Thanks, your article sure makes one feel special

  16. Regina

    September 25, 2011 @ 9:02 am


    I love this. Thanks for the reminder wrapped up in some mind blowing numbers.

  17. mon221

    September 25, 2011 @ 9:59 am


    Not miraculous at all; if you throw a dice with a trillion sides there is 1 in a trillion chances to get any particular number; but 100% chance to get a number.

  18. Chris Angus

    September 25, 2011 @ 10:17 am


    I don’t mean to pick holes in your theory, but doesn’t the average adult meet far more than one person a day? I’d say that through work and an average social life I meet a couple of thousand new people a year that I would actually introduce myself to and shake their hands. For instance, work conferences, 30th Birthday parties etc.

  19. Dennis Groves

    September 25, 2011 @ 11:02 am


    It depends on which definition of miracle, the most common definition and use of the word miracle is definition number 1, which any reasonable person should understand is simply delusion, caused by not understanding natural and scientific laws.

    mir·a·cle noun /ˈmirikəl/  miracles, plural

    1) A surprising and welcome event that is not explicable by natural or scientific laws and is therefore considered to be the work of a divine agency.

    2) A highly improbable or extraordinary event, development, or accomplishment that brings very welcome consequences.

    3) An amazing product or achievement, or an outstanding example of something.

  20. Mike

    September 25, 2011 @ 12:28 pm


    If you exist, then the probability of you existing is 100%.

  21. Aaron Elharar

    September 25, 2011 @ 1:30 pm


    this is basically the most awesome blog post I’ve ever read

  22. baneKiller

    September 25, 2011 @ 2:09 pm


    you are a master.

  23. Markleton

    September 25, 2011 @ 6:02 pm


    Sure it feels good and sounds sciency to make this argument, like quacks claiming that quantum physics proves free will and the soul, or my philosopher friends arguing that P=NP based on . But it’s gibberish. You stopped assigning probabilities to events prior to your ancestors mating – why? Why not also account for the probability of the solar system and earth forming, and life evolving on it?? Gosh, you’re an even bigger miracle now. You can play this game forever with ANY event you choose, but it’s still mathematical nonsense.

  24. DGO

    September 26, 2011 @ 2:48 am


    Enticing to think of Earth as the center of the universe, and yourself as a miracle.

    Realistically though, you could say your existence was an inevitability given enough time, and an infinite universe of possibilities, your specific set of chromosome combinations were bound to come up. Even more likely since your set is a “small” subset of those which produce a living organism, considering unsuccessful combinations would not be able to reproduce.

    Apologies for killing the happy talk.

  25. Stef G

    September 26, 2011 @ 5:51 am


    Wow, thanks!

    I feel much much better now :-)

  26. abinazir

    September 26, 2011 @ 6:24 pm


    Thanks for re-stating the obvious, Mark. When you’ve got something interesting to contribute, do let us know.

  27. abinazir

    September 26, 2011 @ 6:37 pm


    It’s just a rough estimate — no claims to exactitude. Just an exercise in the improbability of it all.

  28. Fred

    September 26, 2011 @ 6:58 pm


    Shuffle a regular deck of 52 cards. Deal yourself a bridge hand (13 cards). What are the chances of getting exactly that hand? Amazing! A miracle!

  29. Isabel1130

    September 26, 2011 @ 6:59 pm


    Probabilities are only meaningful when they are used to calculate an event that has not already occurred.
    When you are talking about an event that has already occurred, i.e. any individuals existence, like a winning poker hand, it becomes meaningless.
    Your individual odds of winning the lottery are poor and yet many people have done it, because the odds of “someone” winning the lottery when sufficient numbers of tickets are sold, are pretty close to one.

  30. The Grey Man

    September 26, 2011 @ 7:06 pm


    “So remember, when you’re feeling very small and insecure,
    How amazingly unlikely is your birth,
    And pray that there’s intelligent life somewhere up in space,
    ‘Cause there’s bugger all down here on Earth.”

    Monty Python, 1983

  31. You-Nique « The Big Think

    September 26, 2011 @ 7:08 pm


    […] are the numbers? Is there even a way to come up with a meaningful estimate? Ali Binazir makes an attempt, starting with a staggeringly big estimate. Then it gets really crazy. Don’t miss it. It […]

  32. hitnrun

    September 26, 2011 @ 7:14 pm


    Really, the only frighteningly unlikely aspect is the Right Sperm Getting Through bit. If you’re an adult man reading this, every time you fidget, millions of sperm reshuffle their position your pants. The Point Man goes back to 1,260,549.

    Compared to that, everything else about your existence is relatively a sure thing.

    It’s really the one thing above all you have to try to forget in order to properly digest a time-travel story. Never mind rescuing the Czar or killing your grandfather: even approaching a group of farmers and shouting “hello!” would set off a chain reaction wiping out all of human history – or at least the proper nouns.

  33. ligneus

    September 26, 2011 @ 7:29 pm


    Then there is the strangeness of things such as: if my mum’s first husband hadn’t come home one night with a bad headache, gone upstairs to lie down and died, and if she as a result hadn’t moved from London to Deal in Kent with her young son, opened up a golfing hotel to keep herself busy and earn a living and there on the golf course met my future papa, I wouldn’t be here today.

  34. orthodoc

    September 26, 2011 @ 7:38 pm


    Monty Python on the enormity of the universe….

  35. catholicgauze

    September 26, 2011 @ 7:49 pm


    Don’t forget to factor in abortion. That decreases the odds of existence alot.

  36. Baba Ganoush

    September 26, 2011 @ 7:50 pm


    Your calculation for the turtle assumes the head of the turtle is out of the water all the time and ignores the fact that a turtle spends only a fraction of its time in the ocean with its head above water. The probability you want = the Probability the turtle sticks its head somewhere out of the water anytime during its lifetime spent in the ocean X the Probability it sticks its head up at a specific place anywhere in the ocean (i.e., through the life preserver). You ignored the first factor and computed the second. As a rough guess, let’s say the turtle swims below the surface most of the time and pokes its head above water only 10% or less of the time in order to breathe. You must therefore multiply your earlier figure by this probability of 0.1, which gives a final probability of 1 in 7000 trillion, or 1 in 7 quadrillion.

  37. Steven Den Beste

    September 26, 2011 @ 7:54 pm


    Sorry, I’m going to rain on the parade. The probability of an event which has already happened is exactly 1.

  38. abinazir

    September 26, 2011 @ 8:01 pm


    Hello, Mr Rain. Please see the addendum at the bottom about “people who are are so damn smart and obsessed with being right.”

  39. Hucbald

    September 26, 2011 @ 8:02 pm


    God knew us all from the beginning, before there was an earth or even a universe, so the chance of us being born is 1:1 mathematically speaking, but really there is no chance… or chaos, for that matter.

  40. knockatize

    September 26, 2011 @ 8:03 pm


    So the Cubs DO have a shot one day.

  41. Walt G

    September 26, 2011 @ 8:14 pm


    The path from the primordial ooze to the spot I take up in phase space is unique and convoluted, no doubt. But there are constraints…

    Not every point in phase space is reachable by any biological process; we can eliminate almost every one. This still leaves us with staggeringly large possibilities.

    Not all forks are equally random. Of the posited four trillion sperm, most cannot fertilize an egg. Some are defective, some have support functions, etc. We’re left with a very large number, just not as big as outlined.

    Some paths are much more likely. People use discretion when mating. They avoid obvious faulty genetics and this removes many possibilities. They seek certain traits (for example, there is some evidence women prefer the smell of men having a different immune history) and this pares the phase space considerably.

    Every generation tightens the focus on one area of phase space. Humans become less like other apes and more defined. A shifting target but a narrower one.

    Still, the number of possible permutations of humans will be mind-boggling higher than those actually expressed. In this universe, anyway. If we consider the many-worlds interpretation of quantum mechanics and then the likelihood of you and me existing becomes certain.

  42. Hillbilly Geek

    September 26, 2011 @ 9:00 pm


    Probability of you being you: 1. Probability of a troll being original and not posting the aforementioned statistic: 0. What’s mindboggling is how many trolls have read this article. That and why their consciousness (such as it is) is parked in front of a computer in a nice, warm coffee shop and not staring at a circling vulture in sub-Saharan Africa.

  43. Alan Brandt

    September 26, 2011 @ 9:06 pm


    …or, God made you who you are. And your parents. And their parents. And theirs, etc.

    Not so random now, is it?


  44. Adam

    September 26, 2011 @ 9:28 pm


    Dr. Manhattan had this exact discussion in “Watchmen.” In the comic, anyway–I forget if it came up in the movie. Whether Watchmen’s author lifted it from another source, I don’t know.

  45. cbunix23

    September 26, 2011 @ 9:37 pm


    I liked the Calvin & Hobbes cartoon about this very subject. He was so proud that he was the pinnacle of millions of years of evolution that came before him.

  46. Ruth H

    September 26, 2011 @ 9:40 pm


    So what are the odds on me? I’m an identical twin. Back in the day when I was born, 1936, I was a 4 1/2 lb preemie, born at home, kept alive by a devoted grandmother. Yet here I am, 74, still 100% here. Well, there are some parts missing and that metal knee….

  47. Mark J

    September 26, 2011 @ 10:07 pm


    To all those commenters who seem to think they’re onto something in stating, “I’m here. Ergo, my chances of existence are 100%,” I have some tragic news for you: this only proves that there is a 100% chance that you are a douchebag.

    What the writer is stating in this amazing bit of mathematical legerdemain is the possibility of any particular person existing is this great. What is the probability that you and the thousands of motorists on the freeway are occupying it at that exact time, that exact group? Another miracle, yet there you are.

    Hey, Stuart Smalley had it right: we’re all special.

  48. Stephen J.

    September 26, 2011 @ 11:26 pm


    It’s certainly true that thinking about the paths not taken, in which something utterly precious to us may not exist or might not have existed, is sobering, and sometimes a decent shot of perspective. Part of appreciating the value of something is to realize how easily we might not have had it. But it’s equally true to point out, along with C.S. Lewis’s Aslan, “No one is ever told what *would have happened*,” and that dwelling on what might have been for too long can distract us from what is right now.

    A universe where our choices matter has to be one of maximum freedom before they’re made, and permanent consequence after they’re made. So both the staggering possibilities of the future and the might-have-beens, and the utter certitude of the present and the what-is-now-and-will-forevermore-be, are things we must keep in mind.

  49. Jerry D.

    September 26, 2011 @ 11:28 pm


    So what are the odds of someone like me leaving a comment? No wait, don’t answer that.

    Ah, so that old line about a turtle sticking it’s head out is older than I thought.

    Those ants that herd aphids. The ones that go out before a storm and move the aphids to the bottom of a leaf to protect them. It’s not a learned action. Ants don’t have the ganglia to manage thought. So the argument is that given enough chances a queen ant would produce a colony of ants that would move aphids under the leaves as a storm approached. What are the odds of that.

    Obviously, because it has happened, 1 to 1. Or the odds that my wife would look up a couple that were good friends thirty years ago, on a “feeling” and find that the husband had died that week. 1 to 1, right?

    Is 1 to 1 a testament to the belief of predestination? It sure sounds like it.

  50. Ravi

    September 27, 2011 @ 12:38 am


    If the universe is infinite (or if they are an infinite number of universes)then each individual is no miracle. You exist in infinite numbers. Sorry about that.

  51. amos

    September 27, 2011 @ 1:38 am


    The probability of existing for something that exist is 1. But that’s looking at the wrong end of the question. The question is what was the probability that you would have come into being starting from the very beginning in a probabilistic but not predetermined cosmos.

  52. echo clerk

    September 27, 2011 @ 3:48 am


    this is complete nonsense. There is no remarkable miracle it makes no sense whatsoever. It simply is.

  53. Dean Cruddace

    September 27, 2011 @ 6:45 am


    Ali, my head hurt at trying to even comprehend some of the numbers so I quite conveniently gave up on trying and focused on the important one, me.

    The likelihood of any of us existing at all through a series of imperfections in nature is enough to make anyones head explode. Thoroughly enjoyed the post (except for the numbers bit).

  54. bk

    September 27, 2011 @ 7:12 am


    Very interesting article, but i will quibble a bit. If you’re going to do the odds of the exact right sperm meeting the exact right egg of your parents, doesn’t that already cover then all the stuff before that being correct? Because that sperm and egg would not exist without the prior odds already being beaten in previous generations. So, i would argue that your estimate should probably stop at that step.

  55. Matt Clary

    September 27, 2011 @ 8:11 am


    In my opinion, this thought experiment is a more compelling reason to be against abortion than if there is a soul. Personally, I am agnostic at best. Agnostic with serious doubts. But the fact that each of us were blessed to exist and be self-aware boggles the brain. Anyone who would steal that should be ashamed of themselves.

  56. D G Myers

    September 27, 2011 @ 8:43 am


    Add one thing more. Each word that you have written above was chosen from the 616,500 words in the English language (according to the OED). But the possible combinations of those words is either infinite or nearly so. You do the math. The chances of a unique historical individual writing just this exact essay are vanishingly small–even smaller than the chances of your existing. Our habits are our habits, but our creative achievements are miracles balanced atop miracles.

  57. TBR

    September 27, 2011 @ 9:14 am


    One of the commenters says that we’re not all that unique. But considering that life is only experienced through the individual consciousness, we’re all absolutely unique. So perhaps our basic stance in life should be deep gratitude and appreciation. Life is a gift. Build from there.

  58. RebeccaH

    September 27, 2011 @ 12:14 pm


    I often tell my grandchildren that they’re the latest in a long line of survivors. I plan to print this off and give them each a copy (with proper accreditation to you, of course). They tend not to recognize the miracles in their lives.

  59. Ali B

    September 27, 2011 @ 2:18 pm


    BK: you may have a point. But the ridiculously large numbers are fun to play with.

  60. Ali B

    September 27, 2011 @ 2:19 pm


    Echoclerk– Some wise person once said that there are two ways of looking at life: you can see everything as being a miracle, or nothing being a miracle. I guess we know your camp.

  61. Ali B

    September 27, 2011 @ 2:20 pm


    Amos: Correct.

  62. Ali B

    September 27, 2011 @ 2:22 pm


    Mark J: well-played, sir.

  63. OSweet

    September 27, 2011 @ 2:31 pm


    Relatedly, I’ve often dizzied myself by, say, speculating on the infinite numbers of potential-but-unrealized brothers and sisters I could have had (in addition to the 3 ‘miracles’ I have to deal with). Also boggles to consider a metaphysical Platonic realm where all potential-but-unrealized beings exist.

    Looking forward, in general: unmiraculous, inevitable.
    Looking backward, from particular instance: miraculous, mind-boggling.

  64. G. Ryan Faith

    September 27, 2011 @ 4:07 pm


    And now for our next trick: the commentariat explores the Anthropic Principle and beats it about the head and shoulders.

  65. waitaminute

    September 27, 2011 @ 5:13 pm


    hey, wait a minute.

    did you just prove that none of us exist at all?

    the lifetime of the universe isn’t long enough for a single positive realization of that low a probability (let alone the billions that have in fact occurred).

  66. Marat

    September 27, 2011 @ 9:55 pm


    Interesting, but is it really so amazing? The fact is the probability of any physical system consisting of trillions of parts being the way it is at any given moment is much smaller then the incredible number mentioned. Let’s pick something random like a solar flare or shape of a cloud on Jupiter. Now start digging into all the events that must have taken place all the way to the Big Bang in order for this flare to happen at this particular time and be of the particular shape and energy distribution. Or the Jupiter cloud to be exactly what it is when it struck your fancy to look at it. This is called observer’s selection and there is little magical about it. As the Universe ages and grows in complexity the probabilities will keep going down. Should a billion years from now another Ali take a moment to reflect upon the wonder of him being him or his cat being his cat the numbers will be smaller yet and just as misleadingly amazing.

  67. The Probability of You Existing at All is Almost NON-Existent.

    September 27, 2011 @ 11:16 pm


    […] side. I am only publishing a small amount of his musings here. You can read his full article here: What are the Chances of You Being Born? and see how he comes up with these […]

  68. tom

    September 28, 2011 @ 9:12 pm


    This is great. It’s very GK Chesterson. We shouldn’t just be amazed at the things the world thinks are wonderous: the graceful dancer or the speedy sprinter. The fact that some us have two legs and can dance or walk at all is an amazing miracle.

    Even if your numbers are mostly pulled from sophisticated guesses, that is no different than the typical business plan.

  69. Weekly Filet #37: My Thirty Slaves. And more.

    September 30, 2011 @ 7:34 am


    […] What are the chances of your coming into being? (Ali Binazir) […]

  70. The Geeks Daily - Page 2 - Digit Technology Discussion Forum

    October 1, 2011 @ 1:16 pm


    […] The Geeks Daily What are the chances of your coming into being? […]

  71. Psilokan.com » Great Moments in Pedantry: The odds of your existence

    November 9, 2011 @ 3:07 pm


    […] The infographic is based on this post by Dr. Ali Binazir. […]

  72. What are the odds? | The Quantum Pontiff

    November 9, 2011 @ 4:02 pm


    […] which the above is just the teaser) posted this morning at BoingBoing. The graphic is based on this blog post by Dr. Ali Binazir, who apparently has an AB (same as a BA) from Harvard, an MD from the UC San […]

  73. David McKee

    November 9, 2011 @ 5:32 pm


    An alternative approach:

    The human genome contains 3 billion base pairs.
    Therefore the human genome has 4^3e9 possibilities.
    This is (approximately) equal to 2^6e9 or 10^1.8e9.

    Granted, many of these will be unviable.

  74. What are the odds that you exist today? [Infographic] | Tag Room

    November 9, 2011 @ 9:02 pm


    […] infographic is based on Ali Binazir’s post which attempts to quantify the probability that you came about and exist as you today and reveals […]

  75. Miracle Odds

    November 9, 2011 @ 9:57 pm


    […] thought of Jobs’ speech today while trying to comprehend calculations that identify the odds we exist and have the opportunity to follow our hearts. The odds are so […]

  76. Nick W

    November 10, 2011 @ 2:03 am


    Another way to look at it that everything living is the product of vast sequence of virtually random events stretching back to the beginning of time. Yes the fact you exist is extremely unlikely, but hardly a miracle.

  77. Amazing, happy info for the day « incredulousinvestor

    November 10, 2011 @ 6:50 am


    […] Love this in all its awesomeness.   First came across it at BB, though it was created by visually at Visual.ly based on a brilliant article by Dr. Ali Benazir. […]

  78. Mokso

    November 10, 2011 @ 7:32 am


    Good article. What I missed was the fact that roughly half of all pregnancies miscarry -roughly half of those happen before the woman even realizes she’s pregnant – increasing the odds ever further.

  79. El milagro termodinámico – Comic Geekos

    November 10, 2011 @ 9:03 am


    […] a continuación las páginas donde el Dr Manhattan explica esto, y luego vayan a este excelente post donde hacen el cálculo de qué tan imposible es que cualquiera de nosotros exista. Qué, no han […]

  80. evolvimus

    November 10, 2011 @ 11:51 am


    Picks: Wie wahrscheinlich ist unsere Existenz?…

    Hier ist ja mal wieder nicht so viel los. Zeit, für ein paar Anekdoten aus der Welt der Wissenschaft. Diesmal gibt es viele mit einem kleinen (ENG) dahinter, für die Links, die auf Englischsprachige Seiten führen … Wissenschaftsblogger Carl Zimmer……

  81. What are the odds? « Osteo[pun]

    November 10, 2011 @ 1:35 pm


    […] I am talking about.  There is a blog post that you should read (or skim through, whatever) called: What are the chances of your coming into being?  It discusses the probability of you existing (as you) today.  Now, I’m not going to get […]

  82. hbh

    November 10, 2011 @ 3:44 pm


    Fun post – my only quibble is about the probability of the right sperm meeting the right egg. You estimate 1 in 400 quadrillion. However, I don’t really care about specific sperm and egg – I only care about specific genetic material. In other words there are 23 chromosomes in the human genome. I need to get the exact set of 23 pairs that creates me. This is equal to 4^23 or roughly 1 in 70 trillion (obviously extremely unlikely but still over 1000X more likely than your example.

  83. Ali B

    November 10, 2011 @ 4:05 pm


    Not sure if I follow. Where does the 4^23 come in? Sperm and egg are both haploid, so it doesn’t make sense to me.

  84. What’s the probability that you exist? « Why Evolution Is True

    November 11, 2011 @ 10:51 am


    […] Ali Binazir went to a Tedx talk in San Francisco and heard some probabilities being bandied about that he considered dubious: One of the talks was by Mel Robbins, a riotously funny self-help author and life coach with a syndicated radio show.  In it, she mentioned that scientists calculate the probability of your existing as you, today, at about one in 400 trillion (4×1014). […]

  85. hbh

    November 11, 2011 @ 12:09 pm


    I was thinking about it like this (although perhaps I’m wrong). For each chromosomal pair there are four potential outcomes – assume the father’s genes are 1,2 and the mother’s pair is A,B – the possible outcomes for the child are 1A, 1B, 2A or 2B. So 4 unique outcomes. With 23 chromosomes I get 4^23.

    Another way to think about it is that a man can only create 2^23 (roughly 8 million) unique sperm cells – anything else is a duplicate.

  86. Ali B

    November 11, 2011 @ 1:55 pm


    I follow the logic now — thanks for that. I’m not sure if it works that way, though, since gametes (eggs and sperm) are haploid — they have 23 chromosomes, not 46. As for sperm uniqueness, it’s quite likely that they’re all unique. Meiotic recombination introduces diversity, and DNA replication in any case has an error rate such that no two cells in the body have the identical 3 billion bases pairs of DNA.

  87. The Odds That You Exist at all Are Basically Zero | proudtobecatholic

    November 14, 2011 @ 7:15 pm


    […] side. I am only publishing a small amount of his musings here. You can read his full article here: What are the Chances of You Being Born? and see how he comes up with these […]

  88. Lyle

    November 15, 2011 @ 6:39 pm


    A man and woman get together and conceive a child. There are 2^23 (8,388,608) possible combinations of chromosomes for the sperm contributed from the father, and likewise, 2^23 possible combinations of chromosomes for the egg contributed by the mother. Therefore there are 2^46 (70,368,744,177,664) possible combinations of chromosomes for the child conceived. Therefore the chance of any one combination being the one conceived is almost zero. Yet one of those combinations did happen. Just like the chances of the next Powerball drawing picking a particular combination of numbers is less than 1 in 195 million, but when the drawing happens, some combination will be drawn. No miracle in either case. Remember that the parents are not trying to get one specific combination of chromosomes, nor is the lottery official trying to get one specific combination on balls.

  89. JohnnyR

    November 15, 2011 @ 10:31 pm


    This was fun and thought provoking and wrong.
    That is not how probability functions.

    Assigning a probability to anything that has already happened is silly because that probability is always 1.

    So this is the real question to be set into an equation:
    What is the probability that someone who cannot be known in the present, will at some point in the future, actually exist, as we would then know?

    There is no solution because the question has no real meaning.

    Probability is not a function of adding up the improbabilities because that introduces permutation and gives a result that is nonsense.

  90. ¿Cuál es la probabilidad de que hayas nacido? | David Austria

    November 18, 2011 @ 9:02 pm


    […] What are chances you would be born *{margin:0; padding:0;} ul{ list-style:none;} #socialbuttonnav {width:90%; […]

  91. Laura

    November 21, 2011 @ 4:59 pm


    Simply wow.

    I’ve been trying to wrap my head around this all day. I keep coming back to a most intelligible and prolific, “wow.”

    It got me thinking, though. I took a course some years ago and remember learning about the Pigeon Hole Principle which, if I remember correctly, seemed to take some of the magic away from seemingly coincidental incidences. I remember something about birthdays. That statistically the chance of any two random people sharing a birthday becomes 100% when the pool of people reaches 366. What’s remarkable though, is that this number goes to 99% with just 50 people (or something like this).

    My question is, would this relate somehow to the amazing statistics you’ve come up with? Could you possible lower the impossible chance of existing with this pigeonhole principle? That somehow the earth and its history was almost required to hold x number of people? And that me existing was simply to fill in a slot?

    I wouldn’t think this would detract from the miracle. After all, what was it that determined the amazing number of pigeonholes?

    Thank you for this mind-numbing information. You have truly made my day.

    Yours Truly,

    – Another Walking Miracle

  92. Wie unwahrscheinlich sind Sie? « Evidenz-basierte Ansichten

    November 21, 2011 @ 5:39 pm


    […] folgende Grafik von visually (?!) visualisiert einen Versuch von Ali Binazir, diese Wahrscheinlichkeit – oder besser Unwahrscheinlichkeit – Ihrer Existenz zu […]

  93. michael glvno

    November 21, 2011 @ 6:53 pm


    Pretty awesome. Super fun to think about. The only major oversight I can see is that your calculations assume that each of our ancestors hold only one position on the family tree, which is patently impossible. If you try to calculate the number of ancestors a person has over the course of 1000 years (50 generations) without taking this ‘pedigree collapse’ into account, you get 2^50 or 1,125,899,906,842,624, which exceeds the number of humans that have ever been born (supposedly about 108bn) by a factor of 10,000. I can only imagine the this issue’s effect on calculations over 150,000 generations.

  94. Ali B

    November 21, 2011 @ 8:00 pm


    The article is not about probability. Sorry you missed the point.

  95. Ali B

    November 21, 2011 @ 8:02 pm


    And the probability of you missing the point is 100%. Now, did you have something original to say, or just regurgitating what the other 90+ pedants commented on?

  96. Tom

    November 21, 2011 @ 10:14 pm


    There must be a troll gene present in the human population. This was an amazing article and thought experiment. It’s amazing how overly critical people can be. They are obviously missing the point of the article. The probability of the specific sperm and egg alone is astronomical. It is obviously impossible to put an exact probability on our existence; this is a thought experiment. Calm down people.

  97. JESUS

    November 21, 2011 @ 10:49 pm



  98. Are You Totally Improbable Or Totally Inevitable? » » Controversial ShitControversial Shit

    November 22, 2011 @ 7:39 am


    […] and blogger Dr. Ali Binazir did the calculations last spring and decided that the chances of anyone existing are one in 102,685,000. In other words, as this […]

  99. What are the odds of you being you? | friskyGeek

    November 22, 2011 @ 12:02 pm


    […] are the chances of you? Whats the probability? Ali Binazir of Harvard did the calculations and found out that its one in 102,685,000. Or better yet – here’s an […]

  100. Probability of boy meeting girl: 1 in 20,000. | One Stat A Day

    November 23, 2011 @ 4:10 pm


    […] Ali Binazir Recommend on Facebook Tweet about it This entry was posted in Uncategorized. Bookmark the […]

  101. Cortland

    November 27, 2011 @ 11:45 am


    The probability of a man and a woman having a child (given the requisite activity beforehand!) is not so bad. That child will BE an individual whom Ali Binazir insists is improbably present reading these words (or anything else). If you see a board fence across a field and shoot a casually lofted arrow at it, the chance you will hit any specific board is small. The chance that you hit ONE of them is MUCH greater.
    This has, incidentally, a relationship with the debate between evolutionists and Creationists. It is more likely that chance gave rise to us than that intelligence did. Why? Doing everything, everywhere, forever, we’re CERTAIN to be where we are.

  102. John Lehman

    November 30, 2011 @ 9:23 pm


    Great article Ali, you live up to your name, you do what a great teacher should do; stimulate thought, wonder and awe.
    Just a question with a spice of humor:

    Did elements of ‘the big bang’ create ‘being’
    did elements of ‘being’ create ‘the big bang’?
    Maybe it’s not an either/or,
    maybe just ‘being-bang’
    if you prefer,‘bang-being’. (Oneness)
    Just because our minds can not grasp the idea of a mystic reality isn’t a proof of non-existence of that reality. We need artist and mystics, people who are in awe of what exists not just people to measure, quantify and manipulate limited aspects of known material reality. The best are those who can do both. Didn’t Einstein love to play the violin in his spare time and Feynman the drum?

  103. Random Thursday: Astronomical Odds, little-bitty Sunny space « Earful of Cider

    December 1, 2011 @ 8:13 pm


    […] at Harvard because a rich relative bribed the Governing Board***—streamlined the math in one hilarious and thought-provoking blog post, and someone made a chart from it (click to […]

  104. bee

    December 3, 2011 @ 5:15 am


    Brill! I love your posts!

  105. Museum of Mysteries » Are you totally improbable or totally inevitable?

    December 8, 2011 @ 4:02 am


    […] and blogger Dr. Ali Binazir did the calculations last spring and decided that the chances of anyone existing are one in 102,685,000. In other words, as this […]

  106. The Immaculate Reception and other Christmas miracles | Think Christian

    December 19, 2011 @ 4:01 am


    […] right. According to Binazir’s calculations, the probability of your existence is approximately 102,685,000. If that’s too large a number to […]

  107. Lizzi:D

    December 26, 2011 @ 4:04 am


    I like this :)

  108. Be Realistic, Demand the Impossible: How #OccupyWallStreet is Redefining Expectations | Orchestrated Pulse

    January 16, 2012 @ 5:42 pm


    […] I’m tired of fighting with people, especially liberals, over impossibilities. Impossibility is merely defined by the limits of human perception. When people stopped believing the Sun revolved around the Earth, it wasn’t because the planets and stars were suddenly different, it was our ability to perceive them that shifted. In fact, life itself is a series of impossibilities. The probability of existing as you are is about 1 in 10^2,685,000. […]

  109. Dan

    February 8, 2012 @ 5:34 pm


    The simplest answer is usually the correct one. This is far from simple…

  110. Back of the Napkin » Blog Archive » Yep. Another fascinating story that will blow your mind.

    March 2, 2012 @ 1:40 am


    […] being inspired by a Harvard Blogger in a topic that truly fascinates me I kinda just want to shout it from the rooftops actually. […]

  111. On the Odds of Your Existence « Patrick F. Clarkin, Ph.D.

    March 18, 2012 @ 1:39 pm


    […] of anyone actually being alive is impossible to calculate, although some have tried. Ali Binazir estimated that the probability of your existence is about 1 in 1o2,685,000.  As he put it: So what’s […]

  112. Tom

    April 25, 2012 @ 12:58 am


    If this event was so rare, then why has it occurred more times than it should have? There are certainly less humans that have ever existed on this earth than the probability that you gave to the event of me existing.

  113. Robert Wampler

    May 22, 2012 @ 3:58 pm


    LOVED this article. I was laying in bed thinking about the Lotto when I started to think, “Haven’t we (every human who has ever been born) already hit the Lotto, so I googled the odds of being born, and I found this great article.

    Question for you, In your calculations, do you account for the fact of TIME? What I mean by this is, there was only one second, maybe even a fraction of a second where the sperm and the egg had a chance to “collide”. In other words, had there been one more “pump” in the humpity hump, we wouldn’t be here.

  114. GIASTAR – Storie di ordinaria tecnologia » Blog Archive » You’ll Be Shocked By How Incredibly Small The Odds Are Of You Being Alive

    June 11, 2012 @ 11:36 am


    […] Ali Binazir illustrates the extremely unlikely chain of events that would have to occur in order for you to be born with this example in a blog […]

  115. TC

    June 30, 2012 @ 11:31 am


    Having made it into existence once (I think!), what are my chances of making it a second time or even third, fourth …. time? If once is seemingly impossible, how about twice? And what about my children?

    I have this theory – if something seemingly impossible happens, then it was certain to happen … repeatedly.

    My suspicion is that I have existed before and will do so again because I am part of the fabric of the universe. Likewise the rest of us.

    It’s just a pity that everything I’ve learnt in this life will apparently have to be re-learnt in the next life.

  116. Antony Lo

    July 21, 2012 @ 7:46 pm


    Hi Ali,

    Nice article. I for one just want you know that I understand that the article is not about the math :)

    I find just thinking about exponential numbers mid blowing… The number of atoms in a human is 10^27 but the whole universe has 10^80…

    It has been funny to see how people put their own perspective and agenda before others…I think if we try to see why and what other people are trying to do or what their intent is, the world would be nicer :)

    Would I be fair to say that the probability I exist is 1 or 100% BUT the probability I existed in this particular way at this time etc etc is your large number?

    And the quibbling about the “small” numbers. Was tempted at first to quibble about these but they make barely a dent in the equation.

    I once read that if you take plancks

  117. Antony Lo

    July 21, 2012 @ 7:49 pm



    If you take Plancks constant, multipled by the seconds since the big bang multiplied the atoms in the universe, you have a probability limit of 10^150

    Don’t know how accurate that is but it is interesting to think about :)

  118. Ali B

    July 24, 2012 @ 3:53 am


    A second is an arbitrary, non-quantized unit of time which can be infinitely subdivided to femtoseconds and smaller. And I’m not sure exactly what the relevance of Planck’s constant is. The point is that there are many moving parts to existence, and the probability of all of our ancestors living to reproductive age is mind-bogglingly small. And yet it is true of every human on the planet — the miraculous present in the mundane all at once.

  119. Why you should never worry about a single thing

    August 13, 2012 @ 11:19 am


    […] a miracle. The odds of you existing are infinitesimally small. According to some Harvard professors so small that the likelihood of you being alive is basically zero. But before your wondrous […]

  120. Chas

    December 14, 2012 @ 9:32 am


    If you were to spend a hard earned dollar on a lottery ticket and wake up the next morning to discover that you and you alone had chosen the winning numbers that entitled you to millions of dollars, a lifetime of luxury, free of worry, stress, hunger, or any discomfort for yourself what would you do? Argue with someone over what was the true mathmatical odds of you being the winner, or would you choose not to waste a precious moment of your new life in useless disagreement over the odds that it had occured? There COULD be an inconceivable number of other human beings here in your place but they are not here and never ever will be here while you are. The moment you took your first breath of life you became one of those most improbable few to do so. You will have a finite number of days in the sun until you draw your final breath and return to the infinite nothingness. The accuracy of the mathmatical odds are intended solely to instill an appreciation for your great fortune to be here. Do not squander the precious moments you have been granted by debating what the real odds of it all may be. Do not squander the gift of life you have been given. The day will come sooner than you may think that you will depart from your fortunate companions and rejoin the multitudes of those who have never spent the briefest of moments in the sun and never, ever will.

  121. 52: Comment avoir plus de chance ? | Neuromonaco

    December 17, 2012 @ 7:31 am


    […] Binazir avait calculé en 20011 qu’on n’avait qu’une chance sur 102 685 000 (un suivi de deux millions […]

  122. suetommy

    January 15, 2013 @ 12:45 am


    Wow! This is a very good reason I like to Stumble Upon. It’s fun and certainly stretches my mind, I don’t need to be critical. My husband and I were playing with numbers since they were becoming so huge. And we began at 100 quadrillion: quentillion, sextillion, septillion, octillion, nonillion,decillion, undecillion, duodecillion, tredicillion, quatrodecillion, quindecillion, sexdecillion, septendecillion, octodecillion, novemdecillion, vigintillion.

    Is there a simple way to count the zeros connected?

  123. It's OK Because Perspectives Can Be Changed

    January 20, 2013 @ 11:27 pm


    […] thing to take for granted: our own existence. The probability of you being you or me being me is staggeringly teensy. If you’re even around to read this, that means we’ve both won the existential lottery. […]

  124. Sunny

    January 25, 2013 @ 4:05 am


    Would someone do the probability of looking like another person almost identically, and NOT be related, NOT remotely a CHANCE that you are related? PLEASE!!!!???? I really am needing to know this….Thank you to whomever takes me up on this….preferably a genetist.(sp?) THANK YOU!!!!!!!!!! I’ll keep checking back to see if any brillant person helps me. :)

  125. Anon

    February 26, 2013 @ 5:24 am


    Great read! I’ve been convinced for a while that the more I learn about the universe and existence the less I understand. The numbers here are great, and so huge that I’m not going to try to amend them, but there are a few things you could add if that’s not unlikely enough for you.
    First, consider that if quite a few very specific fundamental values in the universe were slightly different, life either couldn’t exist or wouldn’t as we know it to. For example, freezing and melting points, lots of complicated particle physics (spins, forces, symmetries, so on), masses, etc.
    Next, you are on this planet, around this star, in this galaxy, in this cluster, in this supercluster. One pertinent example here is that without Jupiter, no life would exist on Earth; the gas giant shields us from many, many catastrophically large impacts from asteroids, comets, etc.
    The point is, while it is undeniably (as this article shows) a miracle that you exist from a biological and social standpoint, 1 in 10^2,685,000 hasn’t even touched the chance that life as we know it exists at all, let alone where and when it does. (The article touches on this with its ‘primordial slime’ comment, but I thought I’d add a little)
    So next time you worry about how your hair looks, don’t.

  126. The Hollow Men » You Existing As You

    April 25, 2013 @ 3:45 am


    […] What are the chances of you coming into being? […]

  127. Just a Freak of Luck - I.WANT.WORLD

    April 26, 2013 @ 12:17 am


    […] — Leave a commentHow lucky do you think you are? Damn very lucky if you consider the amount of humans that had to procreate on your behalf for you to currently take up breathing space. However, let us consider the near […]

  128. johnnyc323

    May 9, 2013 @ 12:01 am


    Thank you, Ali Binazir, what a great article! Of course any really committed evangelical atheist can counter that since the world didn’t particularly need for there to be a “me,” then no necessary condition has been met by the occurrence of “me” in space and time, and so it doesn’t matter how astronomical the odds are, it just doesn’t matter. But I would ask him to consider this: if we were to receive a data packet (whether in electromagnetic waves or physical notation) akin to what Carl Sagan put in that space capsule, what self-respecting scientist wouldn’t proclaim that as proof of intelligent life in the universe? The critical mass of ordered complexity would be deemed to have been met, and quite rightly.

    But doesn’t it seem curious that to some otherwise logical people, a single instance of extremely simple ordered complexity would be proof of intelligent design, while the quintillions of instances of REALLY complex ordered complexity just within their own bodies would not?

    I think I have to be driven by a very powerful and deep-seated antipathy toward religion to blind myself to the overwhelming and indisputable evidence that the universe and everything and everyone in it was hand-coded by SOMEONE. It’s astounding to me that Francis Crick, who ought to know a thing or two about the power of code, could actually NOT believe in God!

    It’s one thing to hate what people have done in the name of religion.Of course this is exactly what Chapter 3 of Genesis warns us about: the forbidden tree isn’t the tree of naked ladies or cocaine, it’s clearly identified as the tree of “the knowledge of good and evil.” Which is the stock in trade of the religious hypocrite: “I know what’s right and I know what’s wrong, and I’ll be the judge of whether you are bad or good!” According to the Bible, this is the worst of all sins, and we should hate the bad things that people do in the name of religion. It’s another thing entirely to abandon all intellectual integrity and insist that there is no God.

  129. rrr

    July 5, 2013 @ 9:14 pm


    You estimated a staggeringly small probability of a person being alive, even without accounting for many other factors as pointed out by several responses.
    However, considering that our consciousness is the result of a unique combination of connected things, we might find that the number of possible unique conscious minds is not such a staggering number. So I would have other parents, on another time, or planet, or universe, but my conscious self would have eventually come into existence. This is a sobering thought that does away with the infinitude of death.
    I wish we understood what makes us conscious well enough to estimate how many of “us” are possible.
    The only problem with this concept is that “I” could be alive in different places at the same time. So is that other “me” really “me”? There is also the non-zero possibility of “me” meeting “myself”.

  130. Katye

    October 1, 2013 @ 4:17 am


    Interesting analysis. If you don’t believe in souls then your existence depends on the exact combination of egg/sperm combination, and all the other ones before it. If there are indeed souls, then you could have been born to another “egg/sperm” combination. No matter how you see it, being born is a miracle. Living is a gift. Don’t waste it!

  131. karim

    November 6, 2013 @ 2:16 pm


    Wow! This is a very good reason I like to Stumble Upon. It’s fun and certainly stretches my mind, I don’t need to be critical. My husband and I were playing with numbers since they were becoming so huge. And we began at 100 quadrillion: quentillion, sextillion, septillion, octillion, nonillion,decillion, undecillion, duodecillion, tredicillion, quatrodecillion, quindecillion, sexdecillion, septendecillion, octodecillion, novemdecillion, vigintillion.

    Is there a simple way to count the zeros connected?

  132. Reasons Why You, the Reader, Are Special « Man Cave Daily

    December 12, 2013 @ 1:55 pm


    […] existing right now is probably the most unlikeliest thing ever. According to NPR, some guy named Dr. Ali Binazir finally took the time to figure out what the odds were that your parents would be exist, meet each […]

  133. Peter Kristensen

    December 18, 2013 @ 8:10 pm


    I think I have to be driven by a very powerful and deep-seated antipathy toward religion to blind myself to the overwhelming and indisputable evidence that the universe and everything and everyone in it was hand-coded by SOMEONE. It’s astounding to me that Francis Crick, who ought to know a thing or two about the power of code, could actually NOT believe in God!

  134. Ali B

    December 23, 2013 @ 9:17 pm


    Peter – it’s equally astounding that someone would anthropomorphize something as vast, mysterious and unfathomable as the universe! Could you be kind enough to share some of this “overwhelming and indisputable evidence that the universe was hand-coded by SOMEONE”? What is the mechanism by which this hand-coding occurs? Is it with ink and compass, a la the illustrations of William Blake, or perhaps something more modern like Python? What shape does this entity take? Where does it reside? Does it have a body? Big claims require big evidence, and the burden of proof is upon you, my friend.

  135. Ag

    January 20, 2014 @ 2:55 am


    This is amazing. I have a question, though it may be odd-ish. What if you are a multiple? The chances of me being born seem astronomical, but what are the chances of 1 or even 2 other people identical (same dna) to me being born as well? I mean the chances when factored into this equation? can it can be factored in? if so how?. @_@ my brain just exploded again.

  136. J.T. Smith

    January 27, 2014 @ 9:59 pm


    I absolutely love this post. I don’t care if the numbers are completely accurate, the end conclusion remains the same… the odds of the history of life on Earth happening in the correct way so that I exist are nearly zero.

    One thing to add, you calculated the odds of all our ancestors needing to have reproduced in the way they did. The odds of life even happening on Earth, and then the odds that the Universe spawned in general is insignificant as well.

    Throw those together, and the odds of us coming into existence as measured from the point of the beginning of the universe is, for all logical purposes, zero.

  137. Terry Hullett

    February 27, 2014 @ 2:45 am


    WOW.. I just congratulated my 9 mo. old grandson for making it here . with Me.

  138. testD

    April 27, 2014 @ 7:18 pm


    Here is the revised infographic, making the case that the “you” mentioned here is actually every single person, so the odds are actually ~100%. Further, most “you”‘s will feel as if they are the most important existence since the history of time unless they understand how things work.


  139. testD

    April 27, 2014 @ 7:39 pm


    Slight correction:


    Corrected infographic on the odds of people existing. The original showed the odds of “you” being born. It makes the case that the “you” mentioned here is actually every single person, so the odds are actually ~100%. Further, most “you”‘s will feel as if they are the most important existence since the history of time unless they understand how things work.

  140. 11 Quotes about Being Yourself Which Actually Mean Something | Twisted Sleeve

    May 12, 2014 @ 8:11 pm


    […] how unlikely it was that you were ever made? (If not, skip down to the infographic at the bottom of this page). Seriously, no one would ever have bet on you being born. But you were. Wouldn’t it be a waste […]

  141. What are the odds? | Rianne Chin

    May 22, 2014 @ 5:19 pm


    […] Via: Ali Binazir […]

  142. Ben

    May 26, 2014 @ 6:41 am


    The probability of the universe being created, our galaxy forming, our solar system forming in just the right place, and our planet being formed in just the right place are not included. This means that the probability of you being you could be hundreds of billions or trillions of times the estimated one in 400 trillion odds.

  143. Ali B

    May 29, 2014 @ 1:02 am


    Ben – thanks for your observation! The article is more an exercise in wonder and gratitude, rather than one of mathematical precision. In short: life is pretty miraculous, and it seems like you get it :)

  144. The Lincoln List

    June 6, 2014 @ 6:03 pm


    […] matter how good or how bad you have it be thankful that you are here . According to scientific research from Harvard, there was  only a 1 in 400 million chance that you were even born. The fact that you are here and […]

  145. Revelations Along the Bosporus | Linda Tries To Figure Out Turkey

    June 28, 2014 @ 5:26 pm


    […] one in 400 trillion chance of even coming into existence at the exact time and place that you did (http://blogs.law.harvard.edu/abinazir/2011/06/15/what-are-chances-you-would-be-born/). That is a crazy, ridiculous miracle that I don’t think many people realize. LIKE SERIOUSLY […]

  146. Ian Wardell

    July 7, 2014 @ 1:19 am


    We have a large number of people in the comments claiming the chances of being born is 1 i.e it is certain. Assuming identity is tied down to a particular sperm fertilizing a particular egg, then this claim is surely transparently false. For example my parents might never have met. How could it be the case therefore that the chance of me being born is 1 (i.e certainty)?

  147. Ian Wardell

    July 7, 2014 @ 2:06 am



    September 26, 2011 @ 6:59 pm

    “Probabilities are only meaningful when they are used to calculate an event that has not already occurred.
    When you are talking about an event that has already occurred, i.e. any individuals existence, like a winning poker hand, it becomes meaningless.
    Your individual odds of winning the lottery are poor and yet many people have done it, because the odds of “someone” winning the lottery when sufficient numbers of tickets are sold, are pretty close to one”.

    You do not justify your assertion in the opening sentence. An extraordinary unlikely sequence of events isn’t rendered wholly unsurprising just because they have already occurred.

    And the point about the lottery is irrelevant. *Someone* will win the lottery,yes, but it is extraordinarily unlikely it will be *you*. If you do win the lottery, and do so every week for a whole year,then you would know that something fishy is going on. It is simply false to say that probabilities are only meaningful before the relevant event(s).

  148. The Probability Of Your Existence | William M. Briggs

    July 7, 2014 @ 2:27 pm


    […] to Harvard Law blogger Ali Binazir, author of Awaken Your Genius, you, dear reader, only have a “1 in 102,685,000” chance […]

  149. Ian Wardell

    July 7, 2014 @ 11:29 pm


    Ali B

    December 23, 2013 @ 9:17 pm

    “Peter – it’s equally astounding that someone would anthropomorphize something as vast, mysterious and unfathomable as the universe!”

    It’s atheists who tend to have an anthropomorphic conceptualisation of God.

    “Could you be kind enough to share some of this “overwhelming and indisputable evidence that the universe was hand-coded by SOMEONE”? What is the mechanism by which this hand-coding occurs?”

    The evidence would be the fact that change in the Universe is not random but exhibits patterns.

    The “mechanism” would be the causal efficacy of the metamind.

  150. Tú no deberías estar aquí | Martha Debayle

    July 10, 2014 @ 11:04 pm


    […] http://blogs.law.harvard.edu Ali Binazir estudió artes en Harvard, medicina en San Diego, una maestría en filosofía en […]

  151. You are, in fact, a miracle | Stephanie Delgado

    July 24, 2014 @ 4:04 pm


    […] who actually try to prove and find answers for questions like this. Enter Ali Binazir who wrote a Harvard Law blog post about this very question. The article also references Mel Robbin’s TEDx Speech which I have […]

  152. mel robbins

    September 7, 2014 @ 4:23 pm


    Ali – I just now stumbled on this – thanks so much for your kind words and also your analysis – I’m working on a new book “The 5 Second Rule” – and will definitely quote you in it! Love your blog. Would also love to talk to you about contributing to a new women’s site I’m launching….email me if you are interested. Mel

  153. Vree

    September 26, 2014 @ 8:41 pm


    The problem with the article is that it is all a giant fallacy. :/ If you call people who point that out “trolls” and smarty-pants you are just ignoring a very basic issue with your logic.

    I mean, I could easily say “there are 7 billion people on the planet today, ergo your chances of being who you are among those people is 1 in 7 billion” and completely ignore the fact that all the other 7 billion other results would all lead to existing people, but does that give a meaningful number for the probably of anything? If you are not careful when choosing those criteria by which you’ll examine the situation then that’s not probablily calculation, it’s only trying to blind people with random large numbers.

  154. L.Rybaczyk

    October 1, 2014 @ 11:25 pm


    For everyone sitting there saying well you exist so the probability is 1… you’re wrong. Please look up posterior probabilities. Just so everyone is clear a posterior probability is “the statistical probability that a hypothesis is true calculated in the light of relevant observations.” If you know anything about Bayesian statistics you’ll see the folly in the birthday equation and the argument that states well an event occurred so the probability is 1.

  155. Day 82: The miracle of our lives | My 360 Day Writing Challenge

    October 3, 2014 @ 9:04 am


    […] The Odds Of You Becoming Exactly You? There is a great image, originally created and posted by Ali Binazir. The conclusion is that the odds that you or I exist at all are zero. To see the image go […]

  156. ¿Qué probabilidad había de que naciéramos tal y como somos? Practicamente, cero - Created by admin - In category: Ciencia - Tagged with: - NotiReal.Com - Informacion al instante

    October 4, 2014 @ 2:38 am


    […] doctor Ali Binazir ha tratado de responder a esta pregunta en un artículo publicado en un blog de Harvard, que también ha sido plasmado en una interesante […]

  157. Lani

    October 16, 2014 @ 8:48 pm


    I don’t normally write comments but this was amazing! My mind was BLOWN when I heard Mel Robbins Ted talk on this and this just takes it further. Thank you! There seems to be two types of people: ones that view this as a miracle and ones that do not. I already knew life was a miracle. Science didn’t need to tell me that but it’s awesome that it can. It’s sad that people still crap on it. All you haters are missing the point. Open your mind a little. I would love to know the probability of the haters actually living happy lives.

  158. The Odds are High that You Worry Too Much | One Happy Dad

    November 9, 2014 @ 11:14 am


    […] grocer, the crazy lady that lives under the local freeway – actually coming into existence, the numbers are truly staggering. So every time a child throws a tantrum or throws up all over you, it truly is […]

  159. JR DeCrotie

    December 8, 2014 @ 9:12 pm


    This was a wonderful article, many people take for granted the life they have been give. So many people complain about being bored, or not having anything to do, when the human mind is so expansive we don’t even understand a fraction of a fraction of the knowledge it would take to comprehend the universe outside ourselves, let alone the infinite universes we can create within our own imaginations.

    everything is made of atoms, when man discovered atoms we wanted to know more. We are the experiment the universe uses, to learn about itself.

    “we are all star stuff”

  160. ¿Qué probabilidad había de que naciéramos tal y como somos? Practicamente, cero – FeedsNews España

    December 20, 2014 @ 10:13 am


    […] doctor Ali Binazir ha tratado de responder a esta pregunta en un artículo publicado en un blog de Harvard, que también ha sido plasmado en una interesante […]

  161. Your Existence Is An Incredible Miracle Of The Universe - funnybuzzfunnybuzz

    March 15, 2015 @ 8:50 am


    […] And then they had to get together at a very particular moment to make you, which had a 1 in 400 quadrillion chance of […]

  162. Happy Monday #49 - Survive at Work

    March 16, 2015 @ 9:44 am


    […] In fact, the mathematical probability of you existing at all is… wait for it… 1 in 102,685,000! (Source) […]

  163. il Palazzo

    March 30, 2015 @ 7:32 pm


    Nice try, but needs some improvement. My birth is as “miraculous” as that of the two eggs I ate today. Okay, maybe less, because poultry breed much faster than humans.
    Tip: “1” followed by a large number of zeros is not neighbour to infinite – far from it. ^_-
    Starting from my birth date, and according to your calculation, there is an unsignificant chance that I wrote what I write now – which should be counted as a miracle. Yet I did it, and I can move on with that . This leads us to the conclusion that your presentation is fundamentally flawed, since on a number of “almost infinite” events so poorly defined, any of them has one chance in an “almost infinite” number to occur. Which tells us nothing, actually. Q.E.D.

    Thank you for your attention.


  164. carpe diem

    May 1, 2015 @ 10:05 pm


    “If you’re reading this, your probability of existing is 1. The probability of all known-to-have-happened to events to have happened is always 1.

    Of course, that assumes that the knowledge is correct; but even the most die-hard skeptic can be absolutely certain that they themselves exist.”

    You’re missing the entire point of this article.

    Entropy is inevitable. The probability that you exist currently may be 1, but 100 years ago the probability was 0, and 100 years from now the probability will (almost certainly) be 0 as well.

    The article does not claim that the odds of ANY human being existing at all is 1 in 102,685,000. It states that the odds you being WHO YOU ARE are 1 in 102,685,000; (based on this numerical model. Which agreed, the numbers could be worked differently.)

    You exist through choice; your parents chose each other. They were in the right place at the right time under the right circumstances to select one another. They used their independent cognitive abilities to choose to reproduce. One, or both of your parents could have just as easily selected a different mate and you simply would not exist.

    Ultimately you’ve chosen to see this article from the perspective of I exist therefore I am. That most certainly is true. However, I exist therefore I am incredibly fortunate to be exactly who I am is equally true, and in my experience makes for a much more enjoyable existence.

    Carl Sagan put it beautifully, describing life as a privilege to be alive at all, and observe the universe.

    You are alive right now. CARPE DIEM.

  165. Ali B

    May 13, 2015 @ 11:09 pm


    Finally, somebody who gets it :) Thanks, Freegrooverider!

  166. The Most Important Thing You’ll Read Today | Revolution Within Reach

    May 27, 2015 @ 3:22 am


    […] It’s been said by Ali Binazir that the odds of you being born to your particular parents, at the time that you were born, with your distinct genetic makeup, is 1:10^2,685,000. Thats a 10 with over 2 million zeros behind it. To put that in perspective, check this example out: […]

  167. Questionmark

    May 28, 2015 @ 2:40 am


    I see many people agreeing that the probability of each of us being born a human being was astronomically small. It just is. I see no one taking it to the next level: If that probability was indeed that close to zero, then how do you explain that I am actually typing this? It cannot be sheer luck. Yes we can explain human existence by an accumulation of highly rare circumstances. But that does not explain that I am one of them, and not gas. There must be something at work that defies probability.

    il Palazzo and other 1:1 believers: you are addressing a different issue. We are not like any other turtle, who has a 1:1 chance of being a turtle. We are that one turtle that is sticking its head through the life preserver. The chance of that happening given you are a turtle is less than 1:1. More likely that someone put that life preserver there on purpose. Frightening thought!

  168. Questionmark

    May 31, 2015 @ 1:15 pm


    Conceded, the chance of me being me, given I am human is of course 1:1. But that distracts from the other question, about me being human given that I consist of molecules. If someone can explain why that is not a turtle in a life preserver, then please rescue me. If not, save our souls.

  169. Esa

    June 2, 2015 @ 9:11 pm


    In doing research for my own writing on celebrating our person and in particular our daily lives, I’ve stumbled on your post (in tandem, after watching Ms. Robbins’ talk and curious about the 1 in 4 trillion number). Just wanted to thank you for the post, and winding it down to a most spiritual inference; a lot of (scientific) supposition ends up leaving any prophetic insight off of the work. So, thank you.

  170. revmatthews

    June 7, 2015 @ 5:23 am


    I was doing my Saturday night study for tomorrow morning’s service (Psalm 131 “I am fearfully and wonderfully made” written by King David, when I ran across your blog post.

    “…How precious also are thy thoughts unto me, O God! how great is the sum of them! 18 If I should count them, they are more in number than the sand…”
    Psalms 139:17-18 (KJV)

    I’m going to challenge my parishioners who Facebook to post a link to your post so they can get an idea of how much of a miracle they actually are…

    I have found that the average Christian’s greatest handicap is the ability to critically understand scientific thought, when actually, contrary to commonly held opinion, the Bible and modern science have quite a lot in common.

    I hope I pronounce your name correctly tomorrow… :D

  171. You are AMAZING because… | Amazing YOU!

    June 11, 2015 @ 5:13 am

  172. It’s a Wonder-filled Life: A Meditation on the Mystery and Unlikely Chances of Our Very Existence : Community in Mission

    June 12, 2015 @ 7:57 pm


    […] side. I am only reporting a small portion of his musings here. You can read his full article here: What are the Chances of You Being Born? and see how he comes up with these […]

  173. WeightLossIsSexy.com

    June 14, 2015 @ 8:33 pm


    Great article. Thank you Ali :)

  174. So You Think You Don’t Matter?? | Laugh, Love, Prosper

    June 29, 2015 @ 7:53 pm


    […] then they had to get together at a very particular moment to make you, which had a 1 in 400 quadrillion chance of […]

  175. Probability? Get off my doorstep. -Rod Fleming's WorldRod Fleming's World

    July 13, 2015 @ 12:51 pm


    […] That led me to do a brief Google and Hey Presto what do you know? I found myself at the blog of an author called Ali Binazir. […]

  176. Ali B

    July 28, 2015 @ 6:19 pm


    High praise indeed, Rev! Hope the parishioners derive some benefit from it. You are also sending them to the fake Harvard Commencement address, yes? :)

  177. Did you know? - You are so cool

    August 1, 2015 @ 11:51 am


    […] The probability of your existing as you, today, at about one in 400 trillion […]

  178. Nick

    September 19, 2015 @ 3:55 pm


    You are a miracle, so is this universe and everything in it, the odds of this all happening the way it did, a universe capable of sustaining life, and you being here reading this, is zero. This is why the Bible tells us only the fool believes there is no God. Because only through intelligence can you have a universe, and concious human beings. It cannot happen any other way. Which is why science tries to come up with multi universe theories, only by trying to eliminate these odds can they take God out of the picture. Sadly for them, there is no multi universes , there is one, and it is capable of sustaining intelligent life,and has everything so precise, everything required for life, so precise, that the odds of it happening by chance are zero.

    People get angry when you mention the odds, because it points to a intelligent designer, something that scares they life out of them because they have gambled everything on this intelligence not existing. The odds are overwhelmingly in favour of their being a all powerful God, and overwhelmingly against there not being a God. The chances of you being here today, right now at this minute in this universe, and all that is required to make that actually happen, is 0, the odds of God not existing is basically 0. This is what the numbers tell us, this is the facts.

  179. London98766789

    September 19, 2015 @ 4:42 pm


    On top of this odds, add in the odds of this universe coming into existence , and having the things like gravity, and atoms set just right after that, even if these things were off by 1%, intelligent life or life, couldn’t exist. The odds of this universe being the way it is by mere chance is 0 if it is the only universe, the only explanation for it being the way it is through chance is if there is a infinite number of universes, and that makes even less sense as you then need a source for these infinite universes, some sort of machine capable of throwing out universes forever. And then the question arises where did this universe creating thing come from. The odds of these things being true get less and less as you go on.

    The fact is, we are faced with overwhelming odds, that life cannot exist as it does, this universe cannot exist as it does, and me and you cannot exist, yet here we all are. Impossible odds of you being here, in a universe that has impossible odds of existing in its current state.

    All the evidence points to a miracle, something that is beyond comprehension, something so far beyond this universe in terms of intelligence and power, that it is impossible for us to understand. This is what the Bible calls God. A infinite power and intelligence that exists outside of space and time, when you add up all the numbers, and realise that there is no chance of this actually happening, no chance of you even being here, or this universe as it is, all that is left is God. This is the data, the cold hard numbers, that do not lie. God has already been proven to exist through the numbers, the odds of things happening as they have.

    If you want to continue to shut out the truth and run away from God, it’s up to you. But you will never find what you are looking for because you are being fooled and you are fooling yourself. You can only run away from the truth for so long, it will catch up with you one day, and then you will have to face the consequences and answer for the way you lived your life, there is no escaping it. Find Jesus Christ, now, today, while you have time, because one day your time will run out and he will not be able to save you.

  180. Ali B

    September 19, 2015 @ 5:59 pm


    Unfortunately, a concept that can be neither proven nor refuted is not scientific. “God” is such a concept. Care to define what that is? Otherwise it’s just fuzz.

  181. mueblesdeoficina

    November 23, 2015 @ 7:43 am


    I was really amazed by the time you spent calculating all those probabilities. I’m not really good at maths but I can tell you that your article is really friendly (probabilities for dummies). It was really great to learn how magical is to be alive. What were our chances? And we are here. Great article.

  182. Brent Routley

    November 25, 2015 @ 11:07 am


    Thanks Ali, You just proved God!

  183. Laks

    December 7, 2015 @ 7:12 pm


    One of the most revered hindu saints has told that there are 3 things a soul can dream of and the first one is specified as being born as a human being… So I appreciate this article. Quite an interesting perspective… For those who disagree it is only a theory. You can read it until you are interested or just ignore it.

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