The Cornell University historian knew his thesis would be unpopular: that the systematic exploitation of slaves underpins the United States’ power and wealth.

Sure enough, after Edward Baptist’s book detailing their abuse at the hands of profit-seeking masters, the role of slave torture in the roots of American capitalism is at the center of a new debate between historians and economists.

At issue is whether the cotton-fueled wealth of the Industrial Revolution was largely a result of increasingly brutal whippings, as Baptist concludes — or biological innovation, as some economists argue.

Baptist’s book, “The Half Has Never Been Told,” was met with derision among some academics when it was published in 2014, and the public scorn continues. At a public debate at Dartmouth College in October, Alan Olmstead, an economist at the University of California at Davis, spun around, waving a pretend magic wand in the air, and dismissed Baptist’s research as “hocus pocus,” according a recent account by the Chronicle of Higher Education.

Olmstead and other prominent economists do not dispute that torture of slaves occurred. But the ratcheting up of torture alone, they argue, could not account for the more than threefold increase in the amount of cotton each slave picked per day between 1801 and 1862.

Instead, Olmstead pointed to another cause in the production uptick: the spread of improved seed varieties that made the cotton easier to pick, including taller, more abundant plants with larger clusters of cotton.

Olmstead cites his own research, conducted with Paul Rhode, an economist at the University of Michigan, as evidence. The pair had published a 2008 paper in the Journal of Economic History that included two charts comparing the picking rates in plantations that grew Upland cotton (the short staple cotton typically grown in Mississippi, Alabama, Louisiana and Texas) vs. Sea Island cotton (a long staple cotton typical of luxury, high-quality cloths that mainly was cultivated along the coasts and islands off Georgia, Florida and South Carolina).

Improved seed varieties of Upland cotton were imported from Mexico, Guatemala and other countries and selected for mass distribution in the American South, whereas Sea Island cotton was not selected for in that way.

Data compiled by Olmstead and Rhode showed that while the Upland cotton picking rate increased more than threefold, there was little change in the Sea Island cotton picking rate over the same time span of 60 years. 

For the economists, this suggests that better seed varieties of Upland cotton was the primary driver behind soaring yields in the 19th century. If torture had played a key role in increased production, they said, the charts would have shown similar increases in productivity of slaves toiling in other crops such as Sea Island cotton, since the rising brutality would presumably have occurred throughout cotton-picking regions.

“If you look at the actual evidence, there is a lot of whipping and punishment and torture in the coast land areas, as well,” Olmstead said of the plantations that grew Sea Island cotton, in an interview. “It may not have been as bad as the other places, but these were not nice places to be.”

Rhode said that their research shows there was a lot of agricultural experimentation that better explains the improved Upland cotton production than increased brutalization of slaves, including enormous efforts made to match the right crops to the soil and combat pests and disease.

“We are not deniers that there was whipping and torture,” Rhode said. “But they were bringing in cotton that was easier to pick. Baptist basically ignored that alternative.”

As the debate continues to rage, Olmstead and Rhode are in the midst of writing a new book about cotton and slavery.

“When you get a large part of a whole profession believing stuff that we think is quite often rubbish, we have an obligation to say that and explain why,” Olmstead said.

Baptist pushed back on Olmstead and Rhode’s rebuttal to his book, arguing that Sea Island cotton plantations used a different system of labor than Upland cotton. In regions producing primarily Sea Island cotton, slaves were given fixed daily quotas, Baptist said in an interview. On Upland cotton plantations, though, the quotas increased regularly.

“Even if some of the uptick came from seeds, it’s still a system driven by force,” Baptist said. Olmstead and Rhode “weigh everything on the seeds. It’s the seeds, the seeds, the seeds. That takes the violence out of the picture.

“The reality is that the U.S. became the world leader of cotton production by the 1850s. This is important for how the Industrial Revolution took place,” he said. “Just about all the cotton picked in the South was picked by the threat of force. Talking about seeds just completely obscures that.”

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