A group of people wants a survey of disease in a population. They calculate that it will cost $100,000 to do this survey properly. They sit down and think about whether their they need the results badly enough to pay $100,000. They decide that, even though the survey would be valuable, they can’t justify the cost. They begin to notice that lots of other groups want the same survey data. They decide that they will do they survey and then sell copies of the results for $5,000, to help pay the costs. Other groups like that idea a lot because they were considering doing the same survey for $100,000. Now, they can get it for $5,000, instead of $100,000. So, they do the survey, sell the results (reducing their own costs), other groups buy it if they think it’s worth the money (reducing their costs from $100,000 of doing the survey themselves to $5,000), and everyone wins.
Then, along comes one group of people saying that “information wants to be free”. Another group says that they “shouldn’t have to pay for it, because they aren’t taking anything away from anybody by getting a copy.” They say the “cost of duplication” is the only relevant cost, and they can use their own photocopier. Soon, everyone follows suit. Nobody pays. The whole system falls apart, leading everyone back to the original situation the next time: each group must pay $100,000 to do this survey themselves, or simply go without the results. The entire world ends up poorer as a result, because collaborative payment falls apart. What copyright does is enable collaborative action, by stopping people from giving away free copies. Piracy allows each group to anonymously opt-out of paying, ultimately undermining the whole system, making the world a much poorer place in the long-run.
We can think of copyright as enabling society to collaboratively fund creative development.