Your theory makes sense to me -- it seems the number of PhDs produced yearly increased greatly since around 1960 [1][2]. Since maintaining a career in science r

Your theory makes sense to me -- it seems the number of PhDs produced yearly increased greatly since around 1960 [1][2]. Since maintaining a career in science requires journal publication, I'm sure this correlates with incredible increases in published results over the past (say pre-1960). Perhaps the mediocre results are published by those wanting to 'look like a productive scientist' without adding much to the knowledge-base. The result being what you're mentioning, and maybe what I'm noticing too. [1] http://www.nsf.gov/statistics/nsf06319/figures/fig02-04.htm http://www.nsf.gov/statistics/nsf06319/figures/fig02-04.htm [2] http://www.nsf.gov/statistics/infbrief/nsf12303/ http://www.nsf.gov/statistics/infbrief/nsf12303/