宋圭武观点181消费函数需要新定义

消费问题是经济最重要的问题之一，消费函数自然也是需要重点研究的经济学内容之一。凯恩斯最早提出消费函数这一概念，他认为，总消费是总收入的函数。库兹涅茨认为，长期消费是收入的一个固定比率，在长期内，平均消费倾向大体稳定。斯密塞斯认为，在短期内，消费是现期收入的函数，并且消费水平随现期收入水平提高而比例减少，而储蓄则随现期收入水平增加而增加；在长期内，消费除受收入影响外，还受其它诸多因素影响。杜森贝里认为，人们的消费存在互相攀比现象，同时，消费还具有一定的惯性。弗里德曼认为，人们的消费主要取决于持久收入。莫迪利安尼通过生命周期说解释消费问题，认为消费者是根据生命周期来安排个人最佳消费。还有一些学者在消费函数中加入理性预期因素，理性预期也成为影响消费的一个重要变量。等等。

总之，现有各种消费函数普遍存在两个方面的问题和不足：一是只考虑一个人现世的消费效用满足，没有考虑到或较少考虑到一个人对来世消费效用的安排；二是更多考虑物质层面的消费效用，缺少精神层面的消费效用考虑。个人认为，一个人的消费函数，在消费效用满足方面，不仅要考虑现世的效用满足，还要考虑来世的效用满足问题，尤其在一些宗教文化浓厚的社会，人们的一些消费，与满足来世效用是高度相关的，甚至更重视来世效用的满足。另外，人们的消费不仅仅是只考虑物质效用的满足，还同时考虑精神效用的满足。在消费成本支出考虑方面，不仅考虑物质成本支出，也考虑精神成本支出，不仅考虑现世的物质成本和精神成本支出，也考虑来世的物质成本和精神成本支出，最终消费成本考虑是这四个方面成本的总和。

与物质收益存在边际递减规律一样，在精神收益方面，也存在边际收益递减规律。比如，一个人荣誉过多，必然增加同一级别荣誉所带来的边际精神收益会递减，除非后面的荣誉等级要比前面的荣誉等级更高，才可能边际收益递增。

在边际收益递减规律作用下，一个人的物质收益和精神收益，二者也存在一定程度边际替代特征。比如在物质贫困状态下，可能一个人会更多通过损失精神收益换取物质收益，一个人在物质富裕情况下，可能会更加注重追求精神收益，慈善也可能会多一些。人们常说，仓廪实而知礼节，衣食足而知荣辱，反映的就是这种情况。还有，一个人随着收入的增加，可能会更加注重消费的相对效用，比如可能会产生一些炫耀性消费等，这也与增加精神收益有关。当然，上述情况也存在诸多例外，结论不能绝对化。

在特定的环境下，消费还存在消费异化问题，即消费过程否定消费者自身存在的真正价值。产生消费异化的原因是多方面的。人性的贪婪自私、不合理的分工结构、制度的不公正、文化的不合理等，都可能导致消费异化问题。好，谢谢，谢谢。

Song Guiwu's view 181 Consumption function needs new definition

Consumption is one of the most important issues in economy, and consumption function is naturally one of the economics contents that need to be studied. Keynes first put forward the concept of consumption function. He believed that total consumption is a function of total income. Kuznets believed that long-term consumption is a fixed ratio of income, and in the long run, the average consumption tendency is generally stable. Smithers believed that in the short term, consumption is a function of current income, and the consumption level decreases with the increase of current income level, while the savings increase with the increase of current income level; in the long run, consumption is affected by many other factors besides income. Duesberg believed that people's consumption exists the phenomenon of keeping up with each other, and at the same time, consumption has a certain inertia. Friedman believed that people's consumption mainly depends on their permanent income. Modigliani explained the consumption problem through the life cycle theory, and believed that consumers arrange their best consumption according to the life cycle. There are also some scholars who add rational expectation factors into the consumption function, and rational expectation has also become an important variable affecting consumption. And so on. In a word, there are two problems and deficiencies in the existing various consumption functions: one is that only one person's present consumption utility is satisfied, without considering or less considering one's arrangement for the afterlife consumption utility; the other is that more consideration is given to the consumption utility on the material level, while less consideration is given to the consumption utility on the spiritual level. Personally, one's consumption function, in terms of consumption utility satisfaction, should not only consider the satisfaction of the present utility, but also the satisfaction of the afterlife utility. Especially in some religious culture society, some of people's consumption is highly related to the satisfaction of the afterlife utility, and even attaches more importance to the satisfaction of the afterlife utility. In addition, people's consumption is not only considered the satisfaction of material utility, but also the satisfaction of spiritual utility. In terms of consumption costs, not only consider the material costs, but also consider the spiritual costs, not only consider the material costs and spiritual costs of the present, but also consider the material costs and spiritual costs of the afterlife. The final consumption cost is the sum of the four aspects of cost. As there is a law of diminishing marginal returns in material income, there is also a law of diminishing marginal returns in spiritual income. For example, a person with too much honor, the marginal spiritual income brought by the increase of the same level of honor will decrease, unless the latter honor level is higher than the former honor level, the marginal returns may increase. Under the law of diminishing marginal returns, a person's material income and spiritual income, both also have a certain degree of marginal substitution characteristics. For example, in the state of material poverty, a person may lose more spiritual income in exchange for material income, a person in the case of material affluence, may pay more attention to the pursuit of spiritual income, charity may be more. People often say, "the grain is full and the etiquette is known, and the clothes and food are enough to know honor and disgrace", reflecting this situation. In addition, with the increase of income, a person may pay more attention to the relative utility of consumption, such as conspicuous consumption, which is also related to the increase of spiritual income. Of course, there are many exceptions to the above situation, and the conclusion can not be absolute. In a specific environment, there is also the problem of consumption alienation, that is, the consumption process denies the true value of the consumer's own existence. The reasons for consumption alienation are many. Human greed and selfishness, unreasonable division of labor structure, institutional injustice, and irrational culture may lead to consumption alienation. OK, thank you, thank you.