I have been struggling to make this decision for the past year. I am a straight A 2nd/3rd year mechanical engineering student and I really can't decide between engineering and physics. My whole life I have always wondered about the universe, and why things work the way they do. I am way more intrigued by things that pertain to theoretical physics than to engineering: I'd rather study the stars, relativity and quantum mechanics than design a more thermally efficient gas turbine (although I do find the study of thermodynamics systems to be very interesting). On the other hand, I am really not sure if I want to devote my whole life to study. I can honestly say that 90% of the time I am awake, I am doing something that relates to academia. When I'm not in class, I am studying, and when I'm not studying I am getting paid to teach other college students math, physics and engineering. When I'm not teaching, I am writing educational handouts that are to be published on the schools website (two of which are already published). I am fine with the way I live now, and I really love learning, teaching, and writing, but I have this fear that I'm going to get to the point to where I don't want to study anymore, and I just want to work. I often find that when I am on breaks such as christmas break, I never find myself wanting to study more (even though I often do study over break to get ahead), and that makes me think that maybe I am not cut out for the life of non-stop studying. I can really see myself enjoying a job as an engineer, although I do not have any experience with engineering aside from classes. The other day my thermodynamics teacher spent half of the class talking about his job maintaining nuclear reactors on submarines and it was really interesting. It makes me think that even though I love physics, maybe I will also love engineering. I think even if I do decide to go the mechanical engineering route, I will always have a strong desire to learn more physics and math. I honestly think that the only thing stopping me from majoring in physics is the money. I would love to live in a world where money doesn't matter, and theoretical physicists live just as comfortably as engineers, but that is not how it is in the real world, which makes this a hard decision. Should I go into physics because it is my passion, or should I go into engineering because I will be able to live a very comfortable life while also doing something I enjoy (just not as much as physics)?