Is there some undiscovered factual necessity for slavery, sexism, racism?

[QUOTE=John Mace]
They don’t need to be slaves to be part of your society.
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No, but you can force slaves to be part of your society. That’s about the only way you can force outsiders to come into your society. Slavery might be an attractive option if you don’t have enough workers in your society.

Western Europeans lost access to sources of slaves as the Middle Ages went on. The Catholic Church said you couldn’t enslave Christians, so as more of the pagans of Europe became Christian, that reduced that source of slaves. They couldn’t take slaves from the Muslim world unless they paid for them- the Muslims had equal or superior military forces, and the flow of slaves there actually went the other way in general.

[QUOTE=Anne Neville]
Slavery does result in a division of labor, which, at least in theory, should get things done more efficiently. It also makes deciding who should do which job less complex, because you don’t have to take into account which of your workers want to do which job- you can just assign them based on who’s best at what, and you don’t have to give people extra incentives to do the distasteful jobs. Slavery also lets a farm or factory owner spend less on modifications to working conditions that make the job more pleasant or less dangerous without increasing production.
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Slaves also tend to do inferior work. Both because of a lack of enthusiasm ( not to mention outright hostility ), and because they are generally kept uneducated and disorganized, to prevent revolts and sabotage. And, becoming dependent on slave labor tends to corrupt society as a whole, and can lead to stagnation or disaster. For example, the slaveowning elite tends to become disdainful of work, or practical accomplishments in general - they have to justify their supposed “right” to own slaves somehow, and looking down on working and building is one way they do that .

The ancient Greeks might have developed the steam engine ( they did have ideas in that direction ) - but being slaveowners, they sneered at any practical applications of their ideas. More recently, slavery ruined the South; even before the war, they were falling farther and farther behind the North. And in trying to justify slavery, they became more and more irrational on the subject, and more and more committed to a self destructive course.

Which brings up another danger of slaveowning; irrationality. In order to justify slaveowning ( or other forms of oppression, for that matter ), the society in question will tend to develop myths about the slaves in question, and believe them, and act on them. And acting on delusions is generally a bad idea. Women have been slaves in all but name in most historical societies, justified by sexist myths about their stupidity and general inferiority - which meant those societies cut themselves off from most of the contributions women could have made.

And slavery also depresses the wages for the laborers of a society, which is bad for them and the economy in general.

[QUOTE=Anne Neville]
Western Europeans lost access to sources of slaves as the Middle Ages went on. The Catholic Church said you couldn’t enslave Christians, so as more of the pagans of Europe became Christian, that reduced that source of slaves. They couldn’t take slaves from the Muslim world unless they paid for them- the Muslims had equal or superior military forces, and the flow of slaves there actually went the other way in general.
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Which helps demonstrate the point that slavery wasn’t necessary. If it had been, Western Europe would have collapsed as the sources of slaves dried up. Or, more likely, they would have just rationalized their way around the rules restricting slavery.

[QUOTE=Acid Lamp]
The necessity of slavery seems to me to correlated to the level of available technology. If you want to have time to create art, literature, politics, philosophy etc… you need the time and resources to support a class of people to do that thing. They have to be able to devote their time to those pursuits, so cannot be busy farming, herding, hunting etc. As technology improves and makes the level of work decrease, the usefulness of the institution of slavery decreases. So in the past, yes, slavery was probably necessary to provide the needed space for the advancement of culture beyond those areas needed to secure the necessities of life.
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The argument I’m making is that slavery wasn’t necessary to support art and literature and so forth; it’s that the surpluses that allowed those things also allowed society to carry the burden of slavery.

[QUOTE=Der Trihs]
Women have been slaves in all but name in most historical societies, justified by sexist myths about their stupidity and general inferiority - which meant those societies cut themselves off from most of the contributions women could have made.
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Disclaimer: I know you said “most” and not “all”, just want to bring this up anyway.

But in some places such as old Athens wasn’t it that women were REVERED, and had to be “protected?” They weren’t saying they were bad people, or weak (in fact if I recall correctly, I learned in history that much of the weakness and inferiority is an 18th/19th century phenomenon and before that it was same result, different reasons), just that it was better if they weren’t in harms way (probably owing to myth and the fact that one woman can carry a couple children but give the sole surviving man a little bit of time and he do a stud impregnation of the state). I’m not saying this mindset doesn’t result in the same philosophy that ends up getting people into messes, I’m just saying I don’t think all of the rationalizations were as negative as you make them out to be.

[QUOTE=Der Trihs]
Which helps demonstrate the point that slavery wasn’t necessary. If it had been, Western Europe would have collapsed as the sources of slaves dried up. Or, more likely, they would have just rationalized their way around the rules restricting slavery.
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Which they did. They changed the rules a little bit and called it “serfdom” instead.