reason

Wilson Quarterly
(http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=8242469)
c/o Ted Newcomb

"Most people make a lot of mistakes when reasoning solo, but in group
settings they tend to be quite skilled at making arguments and
evaluating those of others. One study found that participants got only
about 10 percent of the answers in a tough logic test correct on their
own. When they worked in a group, the scores soared to 80 percent. In
the absence of a challenge from others, people tend to reach for the
most readily available (and often wrong) conclusion. But in groups,
better arguments will win out over time. That the human mind works
best when prodded by others should come as no surprise. Over the
centuries, groups and pairs of people working together have produced
some of the greatest scientific achievements and philosophical
dialogues....Social animals that humans are, it takes partners,
colleagues, and friends to make the most of the mind."