Diversity does not just expand the common ground of consensus. It also increases the larger group’s ability to solve problems. The pioneer in this line of research is the University of Michigan professor Scott E. Page. Page has spent the past twenty years building a convincing case for what he calls the “diversity trumps ability” theory, demonstrating the phenomenon in sociological studies and mathematical models. Take two groups of individuals and assign to each one some kind of problem to solve. One group has a higher average IQ than the other, and is more homogeneous in its composition. One group, say, is all doctors with IQs above 130; the second group doesn’t perform as well on the IQ tests, but includes a wide range of professions. What Page found, paradoxically, was that the diverse group was ultimately smarter than the smart group. The individuals in the high-IQ group might have been smarter, but when it came to measuring collective intelligence, diversity matters more than individual brainpower.