The speculation around the notion of 'dark energy" has a lot in common with that around the notion of "ether".
............................
While Social Darwinism was a misapplication of a misunderstanding of Darwin's theory, it definitely drew its inspiration from Darwinism, and also gained a lot of the respect paid to it, and its ability to be effective, from that connection. It seemed scientific. And it hasn't ever really gone away.

The idea that that "progress" is a meaningful metaphor for human society, rather than, say, growth, or simply change, is one that bears examination.