In fact, even if only a portion of the population became smarter, it might benefit everyone in society. Memory may be the first mental improvement we will be able to engineer, and fortunately it is a less fraught topic than IQ. It has already been improved in mice, such as by enhancing the genes for NMDA receptors in nerve cells. In humans, enhancing those genes could help prevent memory loss in old age, but it could also enhance memory in younger people as well.14
