> They should be trying to grab as much energy as possible, for whatever is it they want to do (as should we) and we should see at least some galaxies going par

> They should be trying to grab as much energy as possible, for whatever is it they want to do (as should we) and we should see at least some galaxies going partially dark. This sort of reasoning was developed in the late 20th century, when economies and populations were rapidly growing everywhere and it seemed like this was just a law of nature. We’re already seeing population growth decline (or reverse) in developed nations, and economic growth has turned out to be much more contingent lately, to say the least. We should probably reconsider the argument that an industrial civilization necessarily develops to building Dyson spheres if the like, when we expect a long-term stable human population of <20B and 2% GDP growth for the foreseeable future. Beyond that, even, is it really unthinkable that a civilization would decide that at some point it had enough stuff for any conceivable purpose? There are other aspects of the 20th-century cultural mindset at work there, too, I suspect.