英語翻譯到20世紀初,全世界已基本消滅了奴隸制.奴隸製作爲人類曾經使用過的一種制度,它的存在有合理性的一面嗎?奴隸制是制

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英語翻譯
到20世紀初,全世界已基本消滅了奴隸制.奴隸製作爲人類曾經使用過的一種制度,它的存在有合理性的一面嗎?奴隸制是制度經濟學家們研究制度的起源、發展及滅亡的一個好樣本.
奴隸制爲什麼最終被廢除?這與因爲隨著經濟的發展和社會的變化,保護奴隸制的成本越來越高,也就是其制度成本越來越高.如在美國南方,長期以來奴隸就是黑人的代名詞.而大部分自由人即白人則不必擔心會成爲奴隸,因爲膚色不同,奴隸都是黑人；即使奴隸逃亡,也很容易辯別、捕獲.然而,隨著自由黑人越來越多,就很難再按膚色區分自由人和奴隸了.結果使保護奴隸制所費的成本增長,淨收益相應下降.從奴隸制的興衰可以看出,任何制度,如果其運行的成本太高,終究是不能長期存在下去的.如巴澤爾所說,如果私人要求國家保護自己的某種行爲,而保護成本卻超過了私人由此而得到的價值,則國家將禁止這種行爲.
奴隸制可能不是一種好制度,但曾經是一種有效率的制度.福格爾在其《艱難歲月：美國黑奴經濟學》一書中提出,撇開農奴制的不道德因素,僅從經濟的角度來上看,農奴制對於發展戰前南方經濟是一種非常有效的制度因素.因爲計量結果表明：1、僅就南方而言,購買農奴的投資所帶來的收益大大高於投資於製造業的收益率；2、南方種植園的規模經濟、有效的管理以及勞動力和資本的大量投入,使得南方種植業生產效益高於北方35%；3、與從事種植業的白人相比,黑奴更爲勤奮,生產效率更高；4、南方城市中從事工業勞動的黑奴的勤奮和生產效率,絕不遜色於那些自由民.城市地區對黑奴需求增長超過農村的事實表明,農奴制與工業化可以和諧並存的.5、黑奴的物質生活條件和待遇並不像人們想像的那樣壞,黑奴一生所生產的90%是歸自己所有的.6、戰前南方經濟並未衰退,而是增長迅速,南方的人均收入增速遠遠高於北方.馬克.布勞格認爲這「可能是美國歷史上有史以來最有爭議的書」.
因此,無論我們今天怎樣評價奴隸制,但是用理性的眼光去分析奴隸制的產生、發展及滅亡的過程和根源對於人類尋找一種好制度是很有意義的.

解答：

你好,請你放心,我在大學裡學的就是英語專業,你的問題就交給我吧
譯文如下：
To the early 20th century, the world has been basically eliminated slavery. Slavery was used as a human system, which exists at a reasonable side of it? Economists have studied the system of slavery is the origin of the system, development and demise of a good sample.
Why slavery was finally abolished? This is because as the economic development and social changes, increasing the cost of protection of slavery, that is, increasing the cost of the system. As in the American South, has long been a synonym for slave is black. Most free people do not have to worry that whites will become a slave, because the different color, slaves are black;Even if the slaves escape, and very easy figuring, capture. However, as free blacks, more and more difficult to distinguish between press freedom and the slaves skin color. The result that the cost of protecting slavery charges increase, net income decreased correspondingly. It can be seen from the rise and fall of slavery, any system, if its running costs are too high, after all, is not long exist. If Barzel said, if a private requires the State to protect their particular behavior, the cost of protection is more than the value of private thus be, then the state will prohibit such behavior.
Slavery may not be a good system, but once an efficient system. Fogel in his "hard times: American slaves Economics," a book made, setting aside the immorality of serfdom factors, only from an economic perspective point of view, serfdom for the development of the antebellum South, the economy is a very effective institutional factors.Because the measurement results showed that:
1, far south, the purchase of serfs the benefits of investment much higher than the rate of return to invest in the manufacturing sector;
2, Southern plantation economies of scale, effective management and labor and capital large number of inputs, making the south than the north crop production efficiency of 35%;
3, and engaged in farming compared with whites, black slaves are more diligent, more productive;
4, the southern city of slave labor in the industrial production of hard work and efficiency, not inferior to those freedmen. Growth in demand for slaves in urban areas than in rural areas the fact that serfdom and industrialization can co-exist in harmony.
5, the slaves of the material living conditions and treatment is not as bad as people think, slave life, 90% of the production of all to himself.
6, the antebellum South, the economy did not decline, but the rapid growth of per capita income growth rate of the South is much higher than the north. Mark. Borlaug that this "may be the most controversial ever in American history books."
Therefore, no matter how the evaluation of slavery today, but with a rational perspective to analyze the emergence of slavery, development and demise of the process and find a good source for the human system is of great significance.