Warning: This is a side note to the discussion at hand. Pass on by if you don’t like history.**
I assume you mean the fact that, for a long time, African American slaves in the south were counted as 2/3 of a person.
This wasn’t actually a determination of how much human they have in them. (It’s semantics, and I understand your argument. Just clearing up a commonly-held misconception.)
The 2/3 counting was actually a tactic to ABOLISH slavery. When the union was formed and, they were trying to write the Constitution, the southern states that had slavery wanted to count slaves as regular people to inflate their census numbers, but, being unable to own land which was the main requirement at the time, slaves could not vote. So, each southern state could then have more seats without a threat of those seats going to an ideologically different group. It was an effort to stack the House with southern delegates who could kill any bill meant to abolish and/or weaken slavery laws, because the south knew the north was intending on abolishing slavery in the Constitution. (Thomas Jefferson actually declared that slavery was morally wrong on all grounds in the Declaration of Independence, but it was stricken from the text because southern states would not join the fight against Britain otherwise, and unity against the common foe was a much more immediate and dire necessity at the time.)
By getting it down to 2/3, the anti-slavery crowd could then petition immigrants to work in the industrializing and commercial north with a better standard of living, tipping the balance in the House toward the north sooner than if slaves counted as 1 person each. While it was not designed as an immediate solution to the slavery question, that compromise, combined with the constitutional amendment process and the law passed to end the slave trade bringing slaves into the United States in 1808, marked the first time in history where a government was substantially set up to outlaw slavery (Kings always could simply ban slavery, but seldom, if ever, did.)
Interesting tidbit that I thought I’d share.
God Bless.
Danny