Certainly the first true humans were unique by virtue of their large brains. It was because the human brain is so large when compared with that of a chimpanzee that paleontologists for years hunted for a half-ape, half-human skeleton that would provide a fossil link between the human and the ape.
Jane GoodallRelated topics
ape brain chimpanzee fossil human large link unique virtue years brainsRelated quotes
The cognitive functioning of a human brain depends on a delicate orchestration of many factors, especially during the critical stages of embryo development-and it is much more likely that this self-organizing structure, to be enhanced, needs to be carefully balanced, tuned, and cultivated rather than simply flooded with some extraneous potion.
Nick Bostrom