Table of Contents

• Dedication to Garrett Hardin
• Tragedy of the Commons
• 1: Cows in the commons
• 2: Fishing the oceans dry
• 3: Littering and dumping
• What is a tragedy of the commons?
• 4: The "common" part
• 5: Portrait of a tragedy
• 6: The tragedy in action
• 7: Why bad things happen to good people
• Solving the Commons Problem
• 8: Types of solutions
• 9: Call to conscience
• 10: Why guilt (conscience) is bad policy
• 11: Coercion
• 12: Privatization
• 13: Private elephants
• Climate and commons
• 14: Climate and commons
• 15: Solving the climate commons
• 16: Cap and trade
• 17: Carbon tax
• 18: Review

Portrait of a tragedy

Usually we think of common rights as a good thing, so why is common benefit such a problem?

Here's what happens -- As a villager, I have a right (like everyone else) to let my goat graze on the village land. But the goat itself doesn't belong to the village. The goat belongs to me. I'm the one that is making goat cheese, and when I have enough cheese, I plan to slaughter it (the goat, not the cheese!) and roast it over a fire. So that means my goat is eating for free from the village lands, and I'm personally getting the benefit of goat products.

So, being a forward thinking villager, I realize that this is a pretty good deal. In fact, why stop with just one? I could get twice the benefit by raising 2 goats. Remember, I don't have to pay for them to eat, so once I've paid for the second one, its pure profit for me.

But of course the rest of the villagers are just as smart as I am. They all realize that double your goat = double your fun. As long as the village has plenty of grazing land, this is fine for everyone.

In fact, several of us decide that 3 goats are better than 2. Now in fact the grazing land is getting a little crowded. Each goat that gets added degrades the land just a little. The soil gets slightly more compacted. The grass get bare in a couple more places. Goat poop starts to build up.

Does this slight degradation cause me, as an individual villager, to decide not to get another goat? Probably not. Remember, the land is getting a little worse because of my one extra goat, but I get the benefit of the entire goat!! Even if that goat gives slightly less milk, and grows slightly smaller, its still basically eating for free, so what the heck?

In fact, it is in my interest (and everyone else's interest) to keep adding goats as long as they can graze enough to make even a slight profit.