“Many of us were worried about how difficult it seemed to make progress in the state that physics was in then. Some people thought that the path to understanding the strong interactions led through the study of the analytic structure of scattering amplitudes as functions of several kinematic variables. That approach really depressed me because I knew that I could never understand the theory of more than one complex variable. So I was pretty worried about how I could do research working in this mess.So the moral of my tale is not to despair at the formidable difficulties that you face in getting started in today’s research… You’ll have a hard time, but you’ll do OK." Steven Weinberg
