The repugnant conclusion is problem in utilitarianism. Utilitarianism concerns itself with the total happiness and well-being of all individuals. Taken to an extreme, this line of thinking leads to societies which are “good” from a purely utilitarian perspective but are nonetheless “repugnant” from a general perspective. This includes situations like slavery. A society of 1000 slaves with 1 unit of happiness a piece is better off, from a purely utilitarian perspective, than a society of 100 non-slaves who each only have 9 units of happiness.

For any perfectly equal population with very high positive welfare, there is a population with very low positive welfare which is better, other things being equal. (“Mere Addition Paradox” 2022)

Bibliography

“Mere Addition Paradox.” 2022. Wikipedia, October. https://en.wikipedia.org/w/index.php?title=Mere_addition_paradox&oldid=1119269650.