Economists say free trade is good because of "comparative advantage". But what is comparative advantage? Why is it good?

This is sometimes considered an arcane part of economics. (Wikipedia defines it using "autarky".) But it's really a very simple idea. Anyone can use it to understand the world and make decisions.

I Islands

Say you live alone on an island.

Each week you gather and eat 10 coconuts and 10 bananas. It takes you five minutes to gather a coconut, and 10 minutes for a banana. Thus, you work 150 minutes per week.

You Need Time to gather one Time You Spend Coconuts 10 5 minute

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