Two years later, Einstein gained the Nobel Prize in Physics, not for basic relativity, but for his discovery of the photoelectric effect. By this time, the 42-year-old physicist had made most of his major contributions to science. Today, about half of AAAS scientists (52%) say this is good time for science, down 24 proportion points from three-quarters (76%) in 2009.

He lived at a time when formal scientific training was scant and there was no system for referring to living things. Plants and animals had frequent names, which various from one location and language to the following, and scientific “phrase names,” cumbersome Latin descriptions that could run a number of paragraphs...