How Probable is Your Being “YOU”

Dr. Hakan Oztunc
6 min readMar 25, 2022

Probability in Creation

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Sometimes unexpected things happen to us in life. We encounter situations that have almost no place in probability calculations. It’s like when the evil Star Wars character Darth Vader declares to the heroic Luke Skywalker, “I am your father.” The revelation is unexpected, and audiences are surprised.

Sometimes, life can feel that way.

This scenario can have different connotations for everyone, and it reminded me of a classical physics question. Suppose you pour a glass of tap water into the ocean. If you think about the size of the ocean, you will also imagine that a glass of water will disappear in it immediately. Five years later, fill a glass of water from another ocean shore on the other side of the world. The question is this: how many water molecules in the second glass came from the first glass? Assuming that there are around a billion cubic kilometers of water in all the world’s oceans, a glass of water is nothing compared to this total volume. Or, to put it mathematically, the probability of a molecule from the first glass being in the second glass is two chances in 1, followed by twenty-two zeros.

But then, there are many molecules in a glass of water: they can have molecules totaling one followed by twenty-five zeros. Assume that a thousand molecules from the first glass are in the second. The probability decreases to only two out of 1019. That is still practically impossible. Going back to Star Wars, what is the probability that the enemy you encounter in the galaxy is your father?

We’d be surprised at the possibility that Darth Vader is Luke’s father, but we wouldn’t be surprised at the birth of a baby. The fact that four babies are born every second worldwide is important here. However, the probability of a baby being born is much lower than that Darth Vader is Luke’s father.

Let’s think of an ordinary person; his name is Joe, and Joe has 46 chromosomes like everyone else. Otherwise, there would be an anomaly in Joe, and then Joe would not be an ordinary person. As everyone remembers from basic biology classes, half of Joe’s chromosomes miraculously come from his mother (Mary) and a half from his father (Jacob). Let’s not forget that his parents, like Joe, have 46 chromosomes from 23…

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Dr. Hakan Oztunc

Statistics Professor, Math Lover, Teaching @UOFT. Author of numerous Math Novels. Always looking to make math fun for everyone. MyBook: https://amzn.to/2M5F5Nz