Most of us would have little trouble labeling the likes of Albert Einstein, Charles Darwin, or Richard Feynman "great" scientists. But when you stop to analyze what makes a great or even a good scientist, you immediately become aware of the complexities and complications of such an evaluation. Great scientists are those who in their lifetimes or afterward have an impact on large segments of a discipline--the wider-ranging the impact, the "greater" the scientist.
Darwin and Einstein have influenced not only biologists or physicists but also philosophers, psychologists, educators, and others. Influence is not just influence but a reflection of the fact that a scientist has shaped, defined, or changed the course of a field. Influential scientists are often those who have the foresight and perspicacity to know what the important problems are before others do and thereby have the advantage of "discovering" or at least setting the stage for...