The Most Common Name in the World is Not Charles Lin. But It Seems That Way To Me.

In 2001 I supervised Charles Lin's Master's Thesis, which was on Private Information Retrieval.

In 2025 I supervised Charles Lin's Master's Thesis, which was on Ramsey Theory.

These are different people. To celebrate the second one's thesis, I took them both out to lunch together. 

A Picture of Charles, Charles, and Bill is here.

I asked ChatGPT about common names.

1) ChatGPT tells me (and I believe them) that the number of people in American people named  Charles Lin is between 200 and 900. The answer pointed out that Charles is common and Lin is common but the combination is not common. 

2) ChatGPT tells me (and I believe them) that the number of people named  John Smith is between 25,000 and 40,000. I've heard it's a common name, but I do not know anyone named that. How is that possible?

3)  I predict that people with last name Smith will be reluctant to name their child John because it is so common. Hence this name will decline. However, I made that same prediction 40 years ago. Maybe it did decline TO 40,000.

4) The most common boys' names in 2025 (so far) in the US are, in order:

 Liam, Noah, Oliver, Theodore, James, Henry, Mateo, Elijah, Lucas, William

According to this website here, the five  most common  boys' names in 1960 (the year I was born), in order, are 

 David, Michael, John, James Robert.

James is the only on both lists. 

I don't have the next  five, though I suspect Henry and William would be on it. I also suspect that Liam and Mateo would not be in the top 100.

5) The most common girls' names in 2025 (so far) in the US are, in order:

Olivia, Emma, Amelia, Charlotte, Mia, Sophia, Isabella, Evelyn, Ava, Sofia

(Should they have Sophia and Sofia both on the list? I would say yes but it is odd.)

 According to that same website,  the most common girls' names in 1960 (the year I was born), in order, are

 Mary, Susan, Linda, Karen, Donna. 

 None of the 1960 name are on the 2025 list. I suspect that would still true for the next 10. 

6) When I was in grade school if the teacher said   Quiet down Bill and Lisa the class went quiet. 

7) The most common first name in the world is Mohammad. The most common last name in the world is Wang. Hence the most common name in the world has to be Mohammad Wang. I've asked students to find the flaw in that logic and all 8 Mohammad Wangs in my class found the flaw. Kudos to them! (Darling says I should always tell you when I am kidding. I am kidding. Only 2 of the 8 Mohammad Wangs in my class found the flaw.)

8) I hope to supervise at least one more Charles Lin before I retire.