社会保障制度自建立以来长期由政府提供,主要缘于社会保障是公共物品的认识。所谓公共物品,是指天气预报、灯塔和国防等具有非竞争性和非排他性的物品。而社会保障却不具有严格意义上公共物品的非竞争性和非排他性这两个特征。在社会保障制度建立之初,由于有资格获取社会保障金的人数有限,社会保障这一产品还未达到充分消费,每增加一个消费 Since the establishment of the social security system, the government has provided it for a long time, mainly due to the fact that social security is the realization of public goods. The so-called public goods, refers to the weather, lighthouses and national defense and other non-competitive and non-exclusive items. However, social security does not have the two characteristics of non-competitive and non-exclusive public goods in the strict sense. At the beginning of the establishment of the social security system, due to the limited number of eligible social security recipients, the product of social security has not yet reached full consumption. For each additional consumption