My own little hell.
I just got back from the library where I checked out a book entitled Discrete Multivariate Analysis: Theory and Practice -- I'm hoping it's more practice and less theory. When I asked the librarian whether I was allowed to check it out, she replied, "Yes, but why would you want to?"
I do not know what "discrete multivariate analysis" is, and I have had very little training in mathematics (some calculus, some statistics, and some other stuff I picked up along the way). There is no chance in hell that I'm going to understand all of the material in this book. I'm hoping the little bit I need is somewhat clear to me after reading it over twenty to thirty times.
If the material is totally out of my ballpark, why would I ever want to check out this book? It all started with these papers published over fifty years ago. I began reanalyzing their results, and that led me to this paper on fitness and recombination. I am now trying to apply a statistical test developed in that paper to a more complex scenario. To do so, I need to figure out how a value in that paper was derived so that I can derive it for my example. That's where the book with the scary name comes in.
Last time I checked, I'm working on a degree in Genetics. I never thought I'd be getting books from the library on mathematical concepts I didn't even know existed when I signed up for this gig. I guess no scientific discipline exists in isolation, and in order to study biology in this modern world you need to have a good handle on the life sciences as well as math, physics, chemistry, and anything else that may intersect your path.