There has probably never been an era in history when intellectuals have played a larger role in society. When intellectuals who generate ideas are surrounded by a wide range of others who disseminate those ideas-- whether as journalists, teachers, staffers to legislators or clerks to judges-- the influence of intellectuals on the way a society evolves can be huge. Trying for years to understand the nature of that influence eventually led me to write the book "Intellectuals and Society," which has just been published.
Intellectuals generate ideas and ideas matter, whether those ideas are right or wrong, and they matter far beyond the small segment of society who are intellectuals. Ideas affect the fate of whole nations and civilizations. Nowhere is that more true than in our own times, when some people make suicidal attacks to kill strangers who have done nothing to them, as on 9/11, because the attackers are consumed with a set of ideas-- a vision-- and driven by the emotions generated by those ideas and that vision.
Whether in war or peace, and whether in economics or religion, something as intangible as ideas can dominate the most concrete things in our lives. What Karl Marx called "the blaze of ideas" has set whole nations on fire and consumed whole generations.
Those whose careers are built on the creation and dissemination of ideas-- the intellectuals-- have played a role in many societies out of all proportion to their numbers. Whether that role has, on net balance, made those around them better off or worse off is one of the key questions of our times.
The quick answer is that intellectuals have done both. But certainly, for the 20th century, it is hard to escape the conclusion that intellectuals have on net balance made the world a worse and more dangerous place. Scarcely a mass-murdering dictator of the 20th century was without his supporters, admirers or apologists among the leading intellectuals-- not only within his own country, but in foreign democracies, where intellectuals were free to say whatever they wanted to.
Given the enormous progress made during the 20th century, it may seem hard to believe that intellectuals did so little good as to have that good outweighed by particular wrong-headed notions. But most of those who promoted the scientific, economic and social advances of the 20th century were not really intellectuals in the sense in which that term is most often used.