
Intellectuals are sometimes accused of being out of touch with the real world. But there is a strong thread of intellectual life that proceeds on the basis of a commitment to linking thought to action, theory to practical outcomes. Karl Marx and John Dewey had at least this in common: they both urged intellectuals to commit themselves to joining the intellectual realm with the solution of humanity's challenges. This isn't a universal view; pure physicists and mathematicians, many philosophers, and many theorists of the arts would adamantly defend the pure search for truth and creativity, no matter what connection these may have to the improvement of humanity. But at least some thinkers and researchers see the purpose of their work as bringing...