H > A > H
I am a big fan of the economist Paul Romer, who is most famous for putting knowledge and the generation thereof at the centre of discussions on growth. Recently, on (roughly) the 25th anniversary of the publication of his paper on Endogeneous Technological Change, he wrote a series of blog posts looking back on some of the issues related to this theory. The most interesting of these was one called “Human Capital and Knowledge”. The post is long-ish, and I recommend you read it