"Historically, the professional intellectual is a very recent phenomenon: he dates only from the industrial revolution. There are no professional intellectuals in primitive, savage societies, there are only witch doctors. There were no professional intellectuals in the Middle Ages, there were only monks in monasteries. In the post-Renaissance era, prior to the birth of capitalism, the men of the intellect — the philosophers, the teachers, the writers, the early scientists — were men without a profession, that is: without a socially recognized position, without a market, without a means of earning a livelihood. Intellectual pursuits had to depend on the accident of inherited wealth or on the favor and financial support of some wealthy protector. And wealth was not earned on an open market, either; wealth was acquired by conquest, by force, by political power, or by the favor of those who held political power. Tradesmen were more vulnerably and precariously dependent on favor than the intellectuals.
The professional businessman and the professional intellectual came into existence together, as brothers born of the industrial revolution. Both are the sons of capitalism — and if they perish, they will perish together. The tragic irony will be that they will have destroyed each other; and the major share of the guilt will belong to the intellectual."
Ayn Rand, For the New Intellectual, 12