Final answer:
Herdsmen always decide to increase the size of their herds in order to maximize their profit. This leads to a tragic situation where each person is locked into a system that compels them to increase their herd indefinitely, resulting in the ruination of the commons.
Step-by-step explanation:
In his essay, The Tragedy of the Commons, Garrett Hardin explains that herdsmen always decide to increase the size of their herds because they seek to maximize their gain and profit. In a commons where resources are shared by all, adding more cattle to their herds increases their profit without any immediate negative consequence. Each rational herdsman concludes that adding another animal to their herd is the only sensible course of action.
This conclusion is reached by every rational herdsman sharing the commons, creating a tragic situation where each person is locked into a system that compels them to increase their herd infinitely in a world with limited resources. This eventually leads to the destruction of the commons. In a society that values the freedom of the commons, individual self-interest ultimately brings ruin to all.