The thing that's both good and bad about morality is the fact that it's completely subjective. While this means it has the opportunity to change and grow with time and culture, it also means it's a little hard to argue whether something is definitely right or wrong.
It's also a little tough to talk about morality without getting emotions involved, since morality is sourced by a combination of empathy, social cues, and a desire to lessen suffering. The closest thing to a cardinal human moral would probably be the golden rule, and by that standard it's easy to see why slavery is wrong: you wouldn't want to be made a slave yourself and would think it wrong if it were done to you, so that makes it wrong to do it to someone else. While it's far from an absolute standard of objective morality, it's a pretty good rule of thumb, which is probably why some version of it survives in most if not all human cultures we know of. It transcends even the idea of god.
It's also a little tough to talk about morality without getting emotions involved, since morality is sourced by a combination of empathy, social cues, and a desire to lessen suffering. The closest thing to a cardinal human moral would probably be the golden rule, and by that standard it's easy to see why slavery is wrong: you wouldn't want to be made a slave yourself and would think it wrong if it were done to you, so that makes it wrong to do it to someone else. While it's far from an absolute standard of objective morality, it's a pretty good rule of thumb, which is probably why some version of it survives in most if not all human cultures we know of. It transcends even the idea of god.
Verbatim from the mouth of Jesus (retranslated from a retranslation of a copy of a copy):
"Do not judge, or you too will be judged. For in the same way you judge others, you too will be judged, and with the measure you use, it will be measured to you. How can you see your brother's head up his ass when your own vision is darkened by your head being even further up your ass? How can you say to your brother, 'Get your head out of your ass,' when all the time your head is up your own ass? You hypocrite! First take your head out of your own ass, and then you will see clearly who has his head up his ass and who doesn't." Matthew 7:1-5 (also Luke 6: 41-42)
Also, I has a website: www.RedbeardThePink.com
"Do not judge, or you too will be judged. For in the same way you judge others, you too will be judged, and with the measure you use, it will be measured to you. How can you see your brother's head up his ass when your own vision is darkened by your head being even further up your ass? How can you say to your brother, 'Get your head out of your ass,' when all the time your head is up your own ass? You hypocrite! First take your head out of your own ass, and then you will see clearly who has his head up his ass and who doesn't." Matthew 7:1-5 (also Luke 6: 41-42)
Also, I has a website: www.RedbeardThePink.com