Is greatness contagious? I think so, along with weakness. Both the splendor and sin of the human spirit are cultivated through the companions with which one invests his time. Who you spend time with is not the only variable in our development, but it is a very crucial one.
Always, when you do a little digging, you will find that those truly admirable were inspired by and (to some degree) sculpted by other great men and women surrounding them. Children whose parents are professional athletes or gifted academically seem to have a greater knack for similar accolades. Sure, one can make a case that it’s all in the genes, but surely this is not the main variable in the equation of greatness.