Systematic SF

Poul Anderson has:

a story in which other galactic races have a much lower IQ than humanity;
a novel in which all detectable races have a comparable IQ but most human beings suddenly get a higher one;
a story in which a newly discovered race is significantly more intelligent than humanity.

With this as with several other themes:

AI;
First Contact;
means of interstellar travel;
interstellar civilizations;
time travel -

- Anderson seemed systematically to examine every possible answer to each of the questions that could be asked.

In Brain Wave, simian intelligence increases until apes learn to speak, as in The Planet Of The Apes. At school, I found some contradictions between science fiction and my religious instruction:

in Heinlein's Starman Jones, an alien animal was able to converse using a limited vocabulary which implied to me that a monkey with an improved brain would also be able to speak whereas a Marist Brother assured me that, in order to speak, any animal would need not an improved brain but an immaterial soul;

one superhero was the reincarnation of an Egyptian prince whereas reincarnation was a heresy;

stories set in the far future did not show Christianity still in existence;

spontaneous healings and even resurrections might result from advanced technology or from alien superpowers rather than requiring a divine intervention.

I am skeptical on reincarnation but, on the other issues, I have gone with more of an sf worldview.