Subjects identified the left-hand image as a woman and the right-hand one as a man. Yet the two images differ only in skin tone. Study by Richard Russell, Sinha Laboratory for Vision Research, MIT.   Skin color differs by sex: women are fairer and men browner and ruddier. Women also exhibit a greater contrast in... Read More

The English psychologist Charles Spearman was the first to argue that a single factor, called "g," explains most of the variability in human intelligence. When observing the performance of children at school, he noticed that a child who did well in math would also do well in geography or Latin. There seemed to be a... Read More