I found this a tough question to ask myself, though I think that’s because I was thinking about it too hard.
My decision to ‘become a scientist’ traces back to the end of high school, and it was not a hard and fast decision. In high school, I did relatively well in most subjects, and more importantly, I was INTERESTED in all my subjects. Straight through to grade 12 I took chemistry, physics, math, english visual art, history, phys. ed., and computer science. My schedule was rather packed, but it was because I just could not say no to any of these topics!
When I was faced with the decision of applying to university I realized I had to choose something, but even with this decision I specifically chose an open program so it would be relatively easy for me to switch to a different one (if needed). In the end, I entered my undergraduate career as a major in Computer Science; I chose the science direction, instead of the visual arts direction or humanities direction, after consultation with my friends and family. It felt that being trained in the sciences would have better applications to the real world, but the main reason I decided on Computer Science was because I found the act of creating a computer program, and working through the problems inherent to that, gave me a great satisfaction. I prided myself when I figured out why my program was broken, or because I was able to increase efficiency. However, after a short time in university I quickly realized that computer science was not for me. Perhaps it was the increased difficulty and length of programs, or maybe I didn’t realize exactly what went into professional programming, but I was turned off. At the same time as this education dilemma I was going through, I was also taking introductory Astronomy as an elective, because I remembered how interesting the subject matter was when I was younger. Out of all my classes, it most drove me to learn more. I quickly switched into the astrophysics program, and I never left!
As an undergrad, I did not identify myself as a scientist. I saw myself as someone who was supremely interested in astronomy and wanted to learn more. In fact, there was nothing else at the university I would have rather learned about. When I got to the end of my undergrad career I chose to continue into graduate school because I was not done learning about astrophysics. I was too interested in the subject matter to stop, and I’m really glad I didn’t; what I learned about astrophysics in my undergrad was only the tip of the ice berg. Now, well into my graduate career, I have started identifying myself as a scientist. I have realized that simply having the interest and drive in a subject to ask questions and seek answers is what a scientist is.
People have asked me many times ‘what are you going to do with a degree in astrophysics?’ Aside from the fact that there are multiple careers for physicists in general, that question has always been moot to me. I went into astrophysics out of interest, not out of career choice. Looking back, I never made a professional or educational decision based on anything other than interest. I was interested in every topic in high school, so I took the classes; I was interested in astronomy, so I did my Bachelor of Science in it; I was interested in black holes, so I decided to study them in graduate school.
I became a scientist, because I was interested.