Nothing interferes with my concentration. You could put on an orgy in my office and I wouldn't look up. Well, maybe once.
Isaac AsimovAfter years of finding mathematics easy, I finally reached integral calculus and came up against a barrier. I realized that this was as far as I could go, and to this day I have never successfully gone beyond it in any but the most superficial way.
Isaac AsimovDuring the century after Newton, it was still possible for a man of unusual attainments to master all fields of scientific knowledge. But by 1800, this had become entirely impracticable.
Isaac Asimov