My argument for why you couldn't is more one of pragmatism than anything else. After 8 hours slogging away in a cubicle, you're unlikely to have the energy to

My argument for why you couldn't is more one of pragmatism than anything else. After 8 hours slogging away in a cubicle, you're unlikely to have the energy to work with the laser-like precision necessary to tackle a scientific problem. Perhaps it is possible in some exceptional cases, but for the vast majority of people I don't see it happening. Plus, science is as much about your interactions with your peers as it is your work. Individuals that aren't highly embedded in a scientific clique are liable to miss important information that would have an impact on your research. You can't develop the same level of social capital as you'd need doing science part-time as a hobby.