'Sup guys, I'm in my final year at the ETH Zurich. For some very short-sighted reasons, in the days of my youth when I was choosing my major, I narrowly chose environmental engineering over physics. After 1.5 / 2 years at the very latest (basically as soon as the STEM common core classes got out of the way), I realized I hated it and had made a huge mistake. Without a doubt, not majoring in physics is the biggest regret/mistake of my life so far. BUT I'd been accepted to a super cool exchange for my third year, and besides, the program itself was only three years initially, so it seemed as if it didn't make a lot of sense to quit then and I might as well go on exchange and make the switch come after I got back. Switching is difficult in Europe, and I could probably have transferred very few credits to physics. Coming back from my exchange, however, not all my credits transferred, and so I was stuck with another semester to wrap things up. I found out that if I took on some extra classes this semester and then kept going next semester, I could additionally graduate with a degree in biotechnology by summer. Figuring if there was even the slightest chance biotechnology was the thing for me it would be worth trying it just in case (because 1 sem is much shorter than 2-3 years), I opted for it, and that is basically where I am now, almost done with the first semester of my final year before graduating with both degrees. If I pull it off, it certainly would be no mean feat -- I don't know anybody who is in the position of graduating with two degrees from the ETH at 22. Biotechnology is better than environmental engineering, but I still feel somewhat... unsatisfied. I still think physics would be far more fulfilling to me. Given that it would mean another 2-3 years to complete a physics program as well, however, at some point, I really need to start weighing costs and benefits. 6-7 degrees before moving to master's programs is a lot. And if you really put biotechnology and environmental engineering together, I feel as if the easiest way to most any career path is forward, not backward. The only thing I can't do is physics. I think a career in astrophysics or something of the sort would definitely be interesting to me, but then the question is how difficult it is to get a fairly theoretical physics position if I'm that late to the game -- I wouldn't graduate with my BSc Physics until 24-25, then finish my MSc 26-27, then PhD 30-31, and only then would I be able to really start looking for jobs/working. That's assuming I never lose time or waste time and manage to get good enough grades in the first place. Not unheard of, but late. And in the meantime, I'd be giving up a lot -- the two bachelor's degrees I already basically have would become worthless, and I'd be moving from a field where I feel I am ahead of most of my competitors or at least well in the game to a highly competitive field where I'm basically 3-4 years behind everyone. And I'd probably still be haunted by regrets that I'll never be as good as I could have been if I'd done physics straightaway. What do you think, is pursuing a passion -- albeit a far-off one -- by switching to physics a good idea, even if I'd be far behind? Or is switching completely unrealistic, and I should just go forward as best I can despite everything, running the risk that I'll always be slightly unsatisfied with it? There is a master's degree program in Neuroinformatics here I could hopefully get into that would probably be my first choice if I were not to switch. I'm well aware that this is definitively my last chance to switch, however.