Culmination And Transcendence

Maybe HG Wells' "The Chronic Argonauts" should have been included in the conceptual sequence outlined in the previous post? It is the earlier, very different and unfinished serial version of The Time Machine. As such, it introduced the idea of a temporal vehicle before The Time Machine did. It also deployed without any fanfare a plot involving an easy to miss circular causality paradox. See here.

This temporal paradox is developed in elaborate detail in several works by Robert Heinlein and his successors, including Anderson. In particular, Anderson's Time Patrol series uniquely combines the two causality paradoxes, circular causality and causality violation. Thus, this series is even more of a culmination of time travel fiction than was indicated in the previous post.

The series also transcends the other works by introducing newer ideas:

not just a single time traveler but a history-spanning organization with, beyond that, a future civilization regularly using time travel and after that again a trans-human species;
temporal alterations resulting not from the activities of time travelers but from random fluctuations in space-time-energy;
an agent who guards the Patrol, tries to anticipate anomalies and to trace influences from other "yets";
not only alternative histories but even an alternative mythology. See here.