The Northern states' argument for slaves not counting fully toward population for representation was primarily based on the view that enslaved individuals were considered property rather than citizens with political rights. Northern delegates argued that since slaves had no voting rights and were treated as property in the South, they should not be counted as full persons for determining representation in Congress. Elbridge Gerry famously questioned why "blacks, who were property in the South," should count toward representation "any more than the Cattle & horses of the North"
. Northern states wanted representation to be based on the free population only, including free blacks, because counting slaves fully would disproportionately increase the political power of the Southern slaveholding states, which would undermine the influence of the North. They also wanted slaves counted for taxation purposes but not for representation, as Southern states wanted the opposite: counting slaves fully for representation but not for taxation
. The resulting Three-Fifths Compromise was a middle ground where three-fifths of the enslaved population would be counted for both representation and taxation. This reduced the political power of slaveholding states relative to counting all slaves fully, but still gave the South more influence than if slaves were excluded entirely from population counts
. In summary, the Northern argument was that slaves should not count fully toward population because they were property without political rights, and counting them fully would unfairly increase Southern political power
. The compromise of counting slaves as three-fifths of a person was a negotiated solution to balance these conflicting interests
