I know that this challenge has been posted before but with all the ACW themed posts that I have read lately I was hoping that opening this thread could create some newer ideas to be shared.
Now to give my own opinion I think that if advances in human psychology are made sooner than in OTL then the concept of individuals that belong to different races have practically the same mental capacity will be accepted sooner. I say this because from my understanding the main logic behind opinions of racial superiority is that people belong to certain races are thought to be more naturally adept at things such as intelligent thought, ethical behavior, physical strength, etc. If scientists in the 1800s due to a POD are somehow capable of understanding that the physical and mental capabilities of an individual cannot be predicted based upon their classified race alone, and they can get their work published and accepted as true, then perhaps the social equality for people of all races could advance sooner. Comments?