São Paulo, Friday, 7 p.m. For those who know the city, these words (São Paulo and Friday) are synonyms for chaos. Now imagine adding rain to the mix. Who in their right mind would attend a Linear Algebra class under such conditions? Me, of course — the nerd of the class. My luck was that I worked just two blocks away from the college building, so skipping class was never an option, logistically speaking. However, apparently, two blocks were enough to leave me completely drenched that night. I walked into the classroom and, to my surprise, there was no one there. I took the opportunity to pick a seat closer to the front and near the wall, where the air conditioning wouldn’t have much effect. I always carried a towel in my bag, along with a gym outfit, just in case I felt motivated to work out. I tried to dry myself as much as possible, but it soon became clear that it wouldn’t make much difference. To avoid getting sick, I decided to change clothes. The problem was that my gym outf...