If a time traveller dropped you off anywhere in the Roman EmpireLasting from 27BC to 476AD, the Roman Empire controlled regions around the Mediterranean in Europe, North Africa and Western Asia. in the year 50AD, slaves might be the first thing you noticed. It is estimated that 10-20% of the population at that time was enslaved.

Being surrounded by people who are owned by others seems like a horrifying idea. But in fact, there are more slaves on the planet today than at any other point in history. And more than half of them are in wealthier countries.¹ Slaves are still everywhere: we just do not notice them.

Now, some are wondering why slavery is still so hard to get rid of.

For many people throughout history, the answer was simple: slavery is part of the human condition. Ancient Greek philosopher AristotleA student of Plato, tutor to Alexander the Great and the father of political philosophy. thought that certain peoples were "natural slaves". They needed a master both to protect them and keep them in line.

When Europeans began settling the Americas in the 16th and 17th Centuries, it became a useful excuse to enslave the local populations. They declared that Native AmericansThe indigenous people of the Americas, who lived in the region before settlers from other places. were natural slaves who needed to be taught how to live properly by civilised Europeans.

Some think slavery is simply impossible to get rid of. They say it has always been part and parcel of human societies.

But others believe this lets us off the hook. They point out that slavery throughout most of history, and in most of the world, meant something very different than it does today.

In China, for example, slaves were something closer to servants. They lived in their master's household and received an allowance. They regained their freedom when they reached a certain age.

Such systems were still unjust and repressivePreventing personal freedom. . But they did not involve the brutal exploitation of slave labour that characterises slavery today.³ This kind of slavery was a European invention.⁴

Yes: Modern slaves mostly provide goods for western consumption: food for our tables, minerals for our smartphones, the clothes we wear. And richer countries are host to more than half of all slaves.

No: Modern slavery tends to come about from war, poverty and gender inequality. It is most prevalent in Africa and eastern Asia. Rich countries are certainly no worse than the rest.

Or... Rich countries have always been the worst offenders. They invented the modern system of slavery with their insatiableImpossible to satisfy. desire for resources, and that desire still fuels it today.