Bigger cars? Supersonic city trips to the other side of the world? Weekends in Antarctica? A week in one of SpaceX’s hotels? High-resolution screens on every wall of your home, plus the AC needed to keep your house cool? Reshape a mountain to improve your view? Transform lead into gold? Mine bitcoin?
If energy were free, I foresee accelerated destruction of nature. At best, the world would become a gigantic park.
Perhaps the reverse, eventually. If costs of space travel dropped enough, we could push polluting industry out into orbit and further, and start repairing Earth. It's impossible now, but if there were little difference on the margin for the businesses between working on the surface and upwell, then businesses would hesitantly say "ah, what the hell, we'll do our stuff up there, you go ahead with your silly environmental programs if that floats your boat". Social progress happens when the market stops caring about it, and doesn't resist it anymore.
The problem would be the demand for resources. Yes, there’s the asteroid belt, but it is far away. Would we get there before we would have dug up the earth? Maybe.
> Jim Crow laws established apartheid, that is, legally enforced segregation. Railroad companies provide an interesting historical example of business incentives. These private companies were often willing, against the political correctness of the times, to sell tickets to both blacks and whites and to not segregate their customers in different cars or compartments. Poor whites and poor blacks purchased second-class tickets, while rich whites and occasionally rich blacks rode in first-class cars. The situation was far from perfect, and violence sometimes erupted, but it was better than the segregationist state-enforced laws that followed.
> A historian of populism observes:
>> More than any other institution, train cars and railroad stations exemplified the modern dilemma of the racial order. They were places where mobile, unsupervised, anonymous travelers met in close quarters. Making the situation more explosive, those whites, including most farmers, who could not afford a first-class ticket met blacks on equal terms. In contrast to the workplace where blacks served white employers, or in the supply store where blacks owed debts to white merchants, in a railroad car blacks and whites paid the same fare for the same right to a seat. Accordingly, whites made the railroads a primary target of the new segregation laws. Reform-minded southerners considered these laws a mark of modern and progressive race relations. (Charles Postel, The Populist Vision, Oxford University Press, 2007, p. 178)
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