From Voltaire's Bastards :
«The more understandable and common reaction of the citizen-expert is defensive. He attempts to turn his prison cell into a fortress by raising and thickening the walls. This padded box may be a cell, but it is also a link within some larger process and is therefore essential. He alone understands and controls the workings of his own box. His power as an individual consists of the ability to withhold his knowledge of cooperation.
In other words, "information" is the currency of a society built upon systems. Once a man has given out his information, he has spent his capital. He therefore doles it out with care. He trades his information for that of others. When threatened, he refuses cooperation -- for example, by exaggerating difficulties or inventing them or moving slowly or offering misleading information. The only real power of expertise lies in retention. The more self-confident the individual, the less likely he has been to choose and isolated and well-defended box. Even so, as Marshall McLuhan put it, "The expert, as such, is full of insecurity. That is why he specializes in order to obtain some degree of confidence."»