25 / 11 / 17
明白了，Aoody！我们只讲 “The Economics of Slavery” 这一节，而且你要逐字稿、口语化、自然、易读，并且能撑满 20 分钟/5 人。下面给你：
演讲总时长：约 19–21 分钟
分工顺序：Aoody（导入与大图景）→ Kevin（Middle Passage：船上经济与人命代价）→ Doit（资本、信贷与利润逻辑）→ Archer（法律与政策：从1808到内陆贩卖、镇压与依赖）→ Louis（收束与反思：数字背后的代价）
Hello everyone. Today our focus is The Economics of Slavery—not just what happened, but why it persisted for so long. I’ll start with the big map of money, markets, and people.
First, picture the triangular trade like a three‑legged conveyor belt. Manufactured goods went from Europe to West Africa. Enslaved Africans were forced across the Atlantic—the Middle Passage—to the Americas. Then plantation commodities—sugar, coffee, tobacco, and especially cotton—flowed back to Europe. That triangle wasn’t just geography; it was a business model tied to global demand. (Encyclopedia Britannica )
The numbers behind it are shocking. Historians estimate about 12.5 million people were embarked from Africa, and roughly 10.7 million survived to be sold in the Americas. Those totals come from voyage‑by‑voyage records that scholars compiled over decades. It is a market statistic—counting human beings as “cargo.” (Encyclopedia Virginia )
Now, why did slavery keep expanding in the United States? One word: cotton. By 1860, raw cotton made up ~60% of all U.S. exports. That export share shows how slave plantations were plugged into world industry, especially British textile mills. In short, global demand paid for local coercion. (American Yawp )
Slavery was not only labor—it was capital. On the eve of the Civil War, the market value of enslaved people in the U.S. was roughly $3 billion (1860 dollars). That made enslaved people one of the largest asset classes in the country. Think of it as a “human balance sheet” that owners could buy, sell, mortgage, and insure. (EH.net)
So the big picture is this: global demand + financial incentives + legal protection made slavery profitable and resilient, even as resistance and abolition grew. Next, Kevin will bring us inside the ships to see how “profit” was squeezed from the Middle Passage—and at what human cost.
[Slide 提示]
Title: Follow the Money
Bullet 1: Triangle model (goods → people → commodities)
Bullet 2: 12.5M embarked / 10.7M disembarked
Bullet 3: Cotton ≈ 60% of U.S. exports by 1860
Bullet 4: Enslaved as $3B “assets”
[Visual 建议] Triangular trade schematic + SlaveVoyages world map; simple export‑share bar. (Encyclopedia Britannica )
When we say “Middle Passage,” we are also talking about cost control—rations, space, disease—managed to maximize sale prices at destination.
Start with how bodies were packed. The famous Brookes ship diagram shows decks drawn like graph paper—human beings measured to fit. After the British Dolben’s Act (1788) tried to limit numbers by ship tonnage, the Brookes’ legal “capacity” was 454 people—and earlier voyages crammed in 600–700+. Even “regulated” stowage meant shoulder‑to‑shoulder confinement. (The Library of Congress )
Conditions? In heat and foul air below decks, fevers and dysentery spread fast. Best estimates put voyage mortality around 12–13%—and that average hides many worse sailings. Sharks followed these ships because so many bodies were thrown overboard. (Encyclopedia Britannica )
Ship surgeons described forced “exercise”—literally “dancing the slaves” on deck with whips and instruments—to keep captives saleable. It was marketed as “health,” but in reality it was inventory management for a human market. (Digital History )
Food and water were strictly rationed. Contemporary testimony reports a pint of water a day as a common allowance during passage, with boiled grains or yams; when storms lengthened voyages, rations shrank and deaths rose. (JSTOR )
Because every death cut profit, crews strung anti‑suicide nets and watched for resistance. Yet people still rebelled or jumped—choosing death over enslavement. The Zong case (1781) lays bare the logic: when water ran low, the crew threw more than 130 captives into the sea and then claimed insurance for “lost cargo.” The legal fight in London wasn’t a murder trial—it was an insurance dispute. Abolitionists publicized it to expose the trade’s brutality. (Royal Museums Greenwich )
So, the Middle Passage was a spreadsheet and a prison: captives were constrained, rationed, and “exercised” to hit a price point on arrival. Next, Doit will show how that logic continued on land—through gins, seeds, banks, and bonds.
[Slide 提示]
Brookes diagram (label key measurements)
12–13% mortality (main drivers: disease, dehydration)
“Dancing the slaves” = forced exercise
Zong = insurance logic exposed
[Visual 建议] Brookes plan; short quote box from a ship surgeon; one‑line explainer of the Zong case. (The Library of Congress )
On land, technology + finance made slavery scale.
First, technology. The cotton gin (1793) made cleaning cotton far faster, locking the South into cotton and deepening dependence on enslaved labor. But the real productivity jump came later from biological innovation—new seed varieties and picking practices. Economic historians find that average daily cotton‑picking rates increased about four‑fold from 1801 to 1862. More cotton picked per person meant higher profits and more demand for enslaved labor to plant, weed, and harvest bigger acreages. (Encyclopedia Britannica )
Second, finance. Enslaved people were mortgaged like property; banks in places like Louisiana accepted human collateral to secure loans, and states even created plantation banks geared to that system. When borrowers defaulted, banks seized and sold people. That’s not metaphor—it’s paperwork. (Yale Department of Economics )
Third, exports and pricing. By 1860, cotton alone ≈ 60% of U.S. exports; Britain’s mills relied on American cotton. That global demand pushed land prices, slave prices, and bank lending upward in a tight loop: higher cotton prices → more borrowing → more land and slaves → more cotton. (American Yawp )
Even insurance plugged in. Marine insurers at Lloyd’s have publicly acknowledged the market’s role in insuring voyages tied to the trade. Risk was priced; profit was pursued. (Lloyds )
So, technology multiplied output, finance multiplied scale, and global demand multiplied cash flows. Archer will now show how laws protected that system—and how policy shifts redirected the trade rather than ending it.
[Slide 提示]
“4×” picking productivity (1801–1862)
Gin vs. seeds: mechanical and biological innovation
Slaves as collateral; plantation banks
Cotton share of exports; British demand
[Visual 建议] Simple line showing picking‑rate index; seed‑to‑output loop; one scan of an antebellum slave mortgage notice (if you choose to include). (NBER )
Did new laws end the economics of slavery? Not immediately—they re‑routed it.
In 1808, the United States banned the international importation of enslaved Africans. That did not free anyone; it closed one pipeline and pushed the market inward. After 1808, a domestic trade exploded—the so‑called “Second Middle Passage”—moving about one million people from the Upper South to the Deep South to feed the cotton boom. We know this not just from narratives but from coastwise slave ship manifests filed at ports like New Orleans. (National Archives )
The law also protected owners across state lines. The Fugitive Slave Acts (1793 and a stronger one in 1850) mandated the arrest and return of escaped people, often without a jury trial, and penalized anyone who helped them. This reduced owners’ “escape risk,” which, in cold financial terms, protected asset values. (Encyclopedia Britannica )
Across the Atlantic, Britain regulated slave shipping with the Dolben’s Act (1788), then abolished the slave trade in 1807, and later used the Royal Navy’s West Africa Squadron to chase traffickers—seizing about 1,600 ships and freeing ~150,000 people aboard over decades. It mattered—but it intercepted only a fraction of the traffic while global demand persisted. (Historic UK )
Meanwhile, Britain’s mills were deeply dependent on U.S. slave‑grown cotton—about 80% of Britain’s raw cotton imports on the eve of the Civil War. When supply collapsed during the war, Lancashire’s “Cotton Famine” (1861–65) brought mass unemployment and poor relief. That crisis shows the world‑system around a single slave crop. (Lowcountry Digital History Initiative )
So, policy mattered—but as long as global industry needed cheap fiber, markets found ways to keep enslaved labor profitable. Laws shifted routes; demand sustained slavery until war and emancipation destroyed it in law.
[Slide 提示]
1808 U.S. import ban → Domestic forced migration (~1M)
Fugitive Slave Acts = cross‑state asset protection
West Africa Squadron figures (ships seized, people freed)
Britain’s 80% cotton dependence → Lancashire Cotton Famine
[Visual 建议] U.S. migration arrows (Upper → Deep South); a clipped slave manifest image; West Africa Squadron map; a Lancashire mill photo. (National Archives )
Let’s stitch this together.
We saw how the triangle worked, how 12.5 million people were forced into a market that priced them by the cubic foot on ships and by the pound of cotton on land. We saw cotton dominate U.S. exports and enslaved people become a multi‑billion‑dollar asset class. And we saw the law—in the U.S. and the U.K.—shape routes, risks, and returns. (Encyclopedia Britannica )
But the heart of this story is human cost. The Brookes diagram is not a diagram at all—it’s a floor plan of suffering. The Zong trial wasn’t about murder; it was about insurance. “Dancing the slaves” wasn’t health; it was price maintenance. Every economic mechanism we mentioned—loans, mortgages, exports, and laws—sat on top of forced labor, family separation, and calculated violence. (The Library of Congress )
So here’s the takeaway I’d like us to leave with: Slavery survived because it made money for powerful actors in a global system. To understand the past honestly, we have to follow the money—across oceans, banks, parliaments, and courts—and never lose sight of the people whose lives were turned into balance sheets.
[Slide 提示]
“Follow the money → see the people”
Three bullets: Global demand / Financial tools / Law & policy
Final image: Brookes plan fading into a cotton bale graphic (symbolizing how bodies were converted into commodities)
下面是上面提纲的逐字版（已口语化）。与上面内容等价，只是更适合直接朗读。
Hello friends. Our topic is The Economics of Slavery. I’ll set up the big picture in three moves—the trade, the numbers, and the profits.
First, the trade. Imagine a conveyor belt shaped like a triangle. Goods from Europe to West Africa; enslaved people forced across the Atlantic; plantation crops—especially cotton—back to Europe. It wasn’t just a route. It was a business model powered by global demand. [Slide: triangle map.] (Encyclopedia Britannica )
Second, the numbers. Best estimates show about 12.5 million people were shipped out of Africa; roughly 10.7 million survived to be sold in the Americas. Those figures are built from ship logs in a massive historical database. [Slide: 12.5M → 10.7M.] (Encyclopedia Virginia )
Third, the profits. On the eve of the Civil War, cotton made up around sixty percent of all U.S. exports. And in 1860, the market value of enslaved people in the United States stood at roughly $3 billion. That tells us slavery wasn’t only labor—it was capital. [Slide: export bar; $3B asset.] (American Yawp )
So the core idea is simple and uncomfortable: global industry paid for local coercion. Kevin will now open the ship’s hatch and show how profits were protected during the Middle Passage.
Let’s step on board. The Middle Passage was a prison managed by a spreadsheet.
Look at the Brookes diagram. Even after the British Dolben’s Act tried to limit numbers, the “legal” capacity was 454; earlier voyages packed 600–700+. A “regulated” ship still meant rows of bodies pressed together. [Slide: Brookes plan.] (The Library of Congress )
Below deck, heat, stench, and disease drove deaths. Scholars estimate 12–13% mortality on the crossing. Sharks often followed these ships—because so many people were jettisoned. [Slide: 12–13% with causes.] (Encyclopedia Britannica )
On deck, crews forced “exercise”—“dancing the slaves”—to keep people saleable. It sounded like health; it was inventory management. Rations were tight—about a pint of water per day appears in testimony—plus boiled grains or yams; storms meant less food and more deaths. [Slide: ration line.] (Digital History )
Profit logic went further. In the Zong case (1781), the crew threw more than 130 people overboard and the owners sued their insurer for the “loss.” The court fight in London wasn’t called “murder”; it was an insurance dispute—and it helped the public see what the trade really was. [Slide: Zong headline.] (Encyclopedia Britannica )
That is the economic core of the ship: pack, ration, insure, and sell. Doit will now show how the same logic scaled up on land through technology and finance.
How did slavery scale? With technology, credit, and global demand.
Technology: The cotton gin (1793) sped up cleaning. Later, new seed varieties and methods made picking faster. Historians tracking plantation records find picking rates rose roughly four‑fold between 1801 and 1862. More picked per day → bigger fields → more enslaved labor demanded for planting, weeding, and harvesting. [Slide: 4× productivity line.] (Encyclopedia Britannica )
Credit: Enslaved people served as collateral. Southern banks, including plantation banks in Louisiana, wrote mortgages that listed people along with land. When loans soured, banks seized and sold them. Finance turned forced labor into leveraged growth. [Slide: “human collateral” box.] (Yale Department of Economics )
Demand: By 1860, cotton ≈ 60% of U.S. exports. British mills needed American cotton; prices, land values, and slave prices moved together. It’s a loop: higher cotton prices → more borrowing → more land and more enslaved people → even more cotton. [Slide: loop arrow.] (American Yawp )
Even the insurance world helped price risk. Institutions linked to Lloyd’s have publicly acknowledged the market’s role in insuring enterprises tied to the trade. [Slide: “insuring the trade”.] (Lloyds )
Archer will now turn to law and policy—how legislation rerouted, protected, or tried to suppress the trade, and how global dependence kept it going.
Did new laws end the profits? Mostly, they redirected them.
In 1808, the U.S. banned transatlantic imports. The result was a huge internal slave trade—the Second Middle Passage—that forcibly moved ~1,000,000 people from the Upper South to the cotton frontier. We can literally read this in coastwise slave ship manifests filed in New Orleans. [Slide: arrows Upper→Deep South; manifest photo.] (New-York Historical Society's WAMS )
The Fugitive Slave Acts (1793, 1850) forced the capture and return of escapees, often without a jury. In hard economics, that reduced “escape risk,” supporting the “asset value” of enslaved labor across state lines. [Slide: law + key clauses.] (Encyclopedia Britannica )
Britain regulated ships (Dolben, 1788), banned the trade (1807), and sent the West Africa Squadron to intercept traffickers—~1,600 ships seized, ~150,000 people freed over decades. It helped—but intercepted only part of a massive traffic while global demand stayed high. [Slide: squadron stats + caution.] (Historic UK )
That demand shows up in Britain’s dependency: by the 1850s–1860s, about 80% of Britain’s cotton came from the U.S. When the Civil War choked supply, Lancashire’s “Cotton Famine” (1861–65) caused mass unemployment—proof that the world economy was entangled with slave‑grown fiber. [Slide: dependency → crisis.] (Lowcountry Digital History Initiative )
To close, let’s keep two truths together.
Truth one: economics. Slavery was a global business: triangle routes, export booms, banks and bonds, insurance and law. Cotton dominated U.S. exports; enslaved people formed a multi‑billion‑dollar asset class. [Slide: three icons—trade, finance, law.] (American Yawp )
Truth two: people. The Brookes plan is a blueprint for pain. The Zong case turned mass killing into an insurance claim. The shipboard “dance” was forced; the ration was minimal; the net was to stop suicide. The numbers are economic; the experience was human. [Slide: Brookes fading into a cotton bale.] (The Library of Congress )
If you remember one line, make it this: Follow the money, and never lose sight of the people. Thank you.
Triangular trade / Transatlantic scope — Encyclopaedia Britannica, Triangular trade; Transatlantic slave trade. (Encyclopedia Britannica )
Totals (12.5M embarked / 10.7M landed) — Encyclopedia Virginia; SlaveVoyages overview. (Encyclopedia Virginia )
Middle Passage mortality (~12–13%) — Encyclopaedia Britannica, Middle Passage. (Encyclopedia Britannica )
Brookes diagram & Dolben’s Act (1788) — Library of Congress item; SlaveryImages annotation. (The Library of Congress )
“Dancing the slaves” / shipboard accounts — Digital History, An Account of the Middle Passage (A. Falconbridge, 1788). (Digital History )
Water ration testimony — Mortality Caused by Dehydration during the Middle Passage, JSTOR. (JSTOR )
Zong massacre (insurance case) — Encyclopaedia Britannica, Zong massacre. (Encyclopedia Britannica )
Cotton share of U.S. exports (~60% by 1860) — The American Yawp, “The Cotton Revolution.” (American Yawp )
Enslaved people valued ≈ $3B in 1860 — EH.Net Encyclopedia, The Economics of the Civil War. (EH.net)
Picking productivity ≈ 4× (1801–1862) — Olmstead & Rhode, NBER Working Paper 14142; Journal of Economic History. (NBER )
Slaves as collateral / plantation banking — Yale Economics paper, Banking on Slavery in the Antebellum South. (Yale Department of Economics )
U.S. 1808 import ban (background & text) — U.S. National Archives overview. (National Archives )
Domestic trade / “Second Middle Passage” (~1M moved) — New-York Historical Society, Women & the American Story. (New-York Historical Society's WAMS )
Fugitive Slave Acts (1793, 1850) — Encyclopaedia Britannica, Fugitive Slave Acts. (Encyclopedia Britannica )
West Africa Squadron results — Historic UK. (Historic UK )
British dependency (~80% U.S. cotton) — College of Charleston digital exhibit. (Lowcountry Digital History Initiative )
Lancashire Cotton Famine (1861–65) — Historic UK. (Historic UK )
U.S. cotton “bale” standard (480 lb statistical bale) — Cotton Incorporated. (Cotton Incorporated )
Gang vs. Task system overview — National Humanities Center, The Varieties of Slave Labor. (nationalhumanitiescenter.org)
语言：保持短句 + 强对比（profit vs. people；law vs. experience）。
时间控制：每人 3:45–4:00，句子停顿自然，遇到数据点稍作停顿。
PPT：每人 1–2 张图 + 3–4 个大字要点即可，图建议用：Triangular trade示意、Brookes图、Zong标题页、Slave manifests截屏、West Africa Squadron数据小卡、Lancashire工厂/救济图。
Q&A 备用点：
为什么技术进步（如种子改良）反而扩大奴隶制？→ 因为单位产量上升→地盘扩张→总劳动量↑，且土地与资本回报驱动扩张。(NBER )
禁止进口后为什么奴隶还增多？→ 内部生育 + 内陆贩卖形成“第二中程航线”。(New-York Historical Society's WAMS )
英国不是反奴了吗？→ 是，但其工业长期依赖美国棉花；海军拦截有效却有限，经济依赖与法律改革并行存在。(Historic UK )
如果你希望我把这些稿子做成配套 PPT（含参考文献页）或给每人生成提示卡（Speaker Notes），告诉我你们的模板风格（浅色/深色、中文/英文标题），我直接按以上结构排好。