What is your favorite color? Do you like yellow, orange, or red? If you do, you must be an optimist(乐观主义者),a leader,an active person who enjoys life,people and excitement. Do you prefer greys and blues? Then you are probably quiet, shy, and （you would rather follow than lead）. You tend to be a pessimist(悲观主义者),At least, this is what psychologists tell us, and they should know, because they have been seriously studying the meaning of color preference, as well as the effect that colors have on human beings. They tell us, among other facts, that we do not choose our favorite color as we grow up—we are born with our preference. If you happen to love brown, you did so as soon as you opened your eyes, or at least as soon as you could see clearly. Colors do influence our moods—there is no doubt about it. A yellow room makes most people feel more cheerful and more relaxed than a dark green one, and a red dress brings warmth and cheer to the saddest winter day. On the other hand, black is depressing. A black bridge over the Thames River, near London,used to be the scene of more suicides(自杀)than any other bridge in the area—until it was repainted green. The number of suicide attempts immediately fell sharply; perhaps it would have fallen even more if the bridge had been done in pink or baby blue. Light and bright colors make people not only happier but more active. It is an established fact that factory workers work better, harder, and have fewer accidents when their machines are painted orange rather than black or grey.