This small survey is a salutary reminder both of how much information citations can convey, and of how much about the science of science we have yet to understand. For example, given that revolutionary papers are quite rare, how might we identify them early? Do innovative papers make connections between areas of knowledge that are not typically made7, or do they get cited early on by papers in remote fields?

In the future, with all the low-hanging fruit plucked, will we see (among the most-cited papers) a relative drop in the percentage of revolutionary papers and a corresponding increase in papers that provide a synthesis of the literature? How quickly does stereotyping of opinion about the importance of a paper happen, and how quickly and how much do such opinions change over time? What proportion of the most important papers across each of these six dimensions might be found among the output of the large majority of scientists with more-average citation profiles?

It would be particularly useful to know whether successful out-of-the-box ideas are generated and defended largely by the most influential scientists or by colleagues lower on the citation rankings. Would the opinion of scientists who cited the top papers that we examined square with the opinions summarized here? Are there other dimensions in addition to the six that we examined that might capture the essence of important work? For example, some respondents pointed to the significance of translational potential and social impact for research, which might have been captured only in part under our Broader Interest dimension. And it would be interesting to know whether there are major differences in the evolution-versus-revolution pattern in the physical sciences.

One way to answer some of these questions would be to survey those who cite the highly cited papers or investigators with more-modest citation rankings. We must continue to hone indices other than citation-based metrics to complement appraisal of scientific accomplishment8.