Changing Human Nature

Although Poul Anderson directly modelled his Psychotechnic History on Robert Heinlein's Future History, the Psychotechnic History is also a direct successor of HG Wells' and Olaf Stapledon's earlier future histories.

"Leonardo da Vinci with his immense breadth of vision, his creative fervour, his curiosity, his power of intensive work, was the precursor of the ordinary man, as the world is now producing him."
-HG Wells, The Shape Of Things To Come (London, 1974), BOOK THE FIFTH, 8, p. 487.

And, elsewhere in this novel, Wells contrasts an irrational, intimidated crowd of the early twentieth century with an intelligent, inquiring crowd of the twenty second century.

In Chapter XI of Olaf Stapledon's Last And First Men (Harmondsworth, Middlesex, 1972), pp. 209-232, "MAN REMAKES HIMSELF."

And Anderson's Psychotechnic Institute tries to remake mankind. See here.

These works are not only fictional histories of future events but also discussions of the way forward for humanity.