This post is a personal story about how I "quitted" math and found data science. I do not intend to encourage anyone to do the same. There are a lot of factors that influence my choice, so please be careful.

## Why not Math?

Three months ago, I was still a Ph.D. student in Mathematics. I was struggling with the decision of dropping out of the program. The process of making that decision was a two-year nightmare. Galois theory, expander graph, chaos theory, discharging method... They are all interesting topics that I spent a lot of time studying them myself. But the more I studied the more I pushed myself away from then reality. I woke up every morning feeling completely lost. I will explain my internal conflict with an example in set theory. The Continuum Hypothesis states that:

`There does not exist a set with a size less than the reals and no set strictly greater than the natural numbers. - Georg Cantor`

If we can find the 1-1 correspondence map between two sets then they have the same size (cardinality). In another word, natural number, integer, and a rational number have the same cardinality, which is infinity. Is there anything bigger than infinity?

The answer is yes! There are sets such as the set of real numbers, that it is impossible to find the 1-1 map between itself and the set of natural number. You can quickly see why by investigating the countability of each set. Natural number set is countable while the real number is not. The Continuum hypothesis emphasis on what truly in-between natural number and real number?

The study of different type of infinity is very interesting. However, the results are impractical to society. Why are there people (Set Theorist) spend their whole life study about infinity? I can't answer this question myself. I respect mathematician in general because of their unspoken contribution to science or art. Nonetheless, my mentality is not built for processing this 9-to-5. This truth took me a long time to learn.

One important point is that my family lives under the poverty line. They always support my career decision and I am grateful about that. But as the eldest son in the family, I still feel seriously bad for not being able to provide. Graduate-level pure math is a form of art which takes seven years to master. On the contrary, a Ph.D. in pure math is unhireable in most industry and also competitive in academia. Thus, it is not sensible for me to continue.

## Let says that family was not an issue. Would you continue?

I started the Ph.D. program in math with full funding. I imagined myself finished the program with my head held high in a standing ovation. However, Ph.D. in math takes more than just the liking. It requires a lot of commitment, sacrifice, and mental capability. I was not ready for it at all. I came to the battle arena with just a wooden sword.

In the very first month of grad school, I suffered from ** imposter syndrome**. My school was one of the tops of the nation in abstract algebra. I freaked out by my classmates because they always "quietly nod their head" whenever the teacher wrote, both literally and metaphorically,

**Greek**on the board. I worked my butt off to get better but the progress is hardly noticed. I was a big fish in a small pond before I came, but here I am nobody in the sea of sharks and whales. By the end of the first years, I got an existential crisis. I was so depressed that I sent out apology letters to some professors in my undergrad, telling them that I was a failure, I did not live up to their expectation. Luckily, I managed to pass all the classes and maintain good standing in the program. However, I felt tired and my head was cloudy all the time. I learned that something was not right. But, I was too afraid to think about it.

## What makes me choose data science?

After the trauma, I reevaluated my goal in life. I tried to convince myself about opportunities outside academia. However, I felt ashamed for not be able to finish what I started. One day, I saw a post from a Ph.D. fellow that changed my mind,

The advice soothed the wound. A few days later, I talked to the department chair about my situation. This was four months before my graduation.

I looked for a job that required a Master in a quantitative field and Data Science caught my attention. I know a little bit Python, combinatorics, and graph theory. I just hoped that my time here would not be wasted.

## How do I feel now?

I came back home after graduation and live with my parents and three younger siblings. It takes me a while to adjust my daily routines. I have been gone for two years and a lot of things had changed. My brother had grown a lot. He endures the anxiety disorder and gave my parents a headache many times. I just wish that I could be here sooner to be his brother. I also had a lot of mom food which is like heaven compared with what I ate back then.

I started a Data Science program at Flatiron a week ago. I had to pay a lot of money to get in but I feel good about it so far. The program is challenging enough to be fun. There is a lot of logical thinking in programming which is similar to math. Although the curriculum is condensed and laborious, the staffs are very helpful. They just graduated from the program so they understand our feeling and give a lot of input. The students here came from different backgrounds: oil and gas, geology, IT, teacher,... We have one thing in common that we all try hard to advance our career.

## Ending notes

I never regret my two years in graduate school. I made a bunch of smart friends and experienced college life. I also have learned a lot about myself through hardship.

My piece of advice for friends out there who are still finding their passion. *It's hard to change but it worths the try!*

## Discussion