Monopolistic competition is the only market structure that features many sellers.

Many objects in daily use have clearly been influenced by science, but their forms and functions, their dimensions and appearances, were determined by technologists, artisans, designers, inventors, and engineers using nonscientific modes of thought. Many features and qualities of the objects that a technologist thinks about cannot be reduced to unambiguous verbal descriptions; they are dealt with in the mind by a visual, nonverbal process. In the development of Western technology, it has been nonverbal thinking, by and large, that has fixed the outlines and filled in the details of our material surroundings. Pyramids, cathedrals, and rockets exist not because of geometry or thermodynamics, but because they were first a picture in the minds of those who built them.

The creative shaping process of a technologist's mind can be seen in nearly every artifact that exists. For example, in designing a diesel engine, a technologist might impress individual ways of nonverbal thinking on the machine by continually using an intuitive sense of rightness and fitness. What would be the shape of the combustion chamber? Where the valves should be placed? Should it have a long or short piston? Such questions have a range of answers that are supplied by experience, by physical requirements, by limitations of available space, and not least by a sense of form. Some decisions, such as wall thickness and pin diameter, may depend on scientific calculations, but the nonscientific component of design remains primary.

Design courses, then should be an essential element in engineering curricula. Nonverbal thinking, a central mechanism in engineering design, involves perceptions, the stock-in-trade of the artist, not the scientist. Because perceptive processes are not assumed to entail "hard thinking", non- verbal thought is sometimes seen as a primitive stage in the development of cognitive processes and inferior to verbal or mathematical thought. But it is paradoxical that when the staff of the Historic American Engineering Record wished to have drawings made of machines and isometric views of industrial processes for its historical record of American engineering, the only college students with the requisite abilities were not engineering students, but rather students attending architectural schools.

If courses in design, which in a strongly analytical engineering curriculum provide the back- ground required for practical problem-solving, are not provided, we can expect to encounter silly but costly errors occurring in advanced engineering systems. For example, early models of high-speed railroad cars loaded with sophisticated controls were unable to operate in a snowstorm because a fan sucked snow into the electrical system. Absurd random failures that plague automatic control systems are not merely trivial aberrations; they are a reflection of the chaos that results when design is assumed to be primarily a problem in mathematics.

The author write this passage mainly to______.

A．introduce a new idea.

B．stress the importance of nonverbal thinking.

C．criticize the education for omitting an important part of knowledge.

D．propose a suggestion.

A、the costs that parties incur in the process of agreeing and following through on a bargain.

B、the uncompensated impact of one person's actions on the well-being of a bystander.

C、the proposition that private parties can bargain without cost over the allocation of resources.

D、a market equilibrium tax.

A、Government should tax goods with either positive or negative externalities.

B、Government should tax goods with negative externalities and subsidize goods with positive externalities.

C、Government should subsidize goods with either positive or negative externalities.

D、Government should tax goods with positive externalities and subsidize goods with negative externalities.

A、private costs exceed social costs at the private market solution.

B、externalities cannot be corrected without government regulation.

C、social costs exceed private costs at the private market solution.

D、production externalities lead to consumption externalities.