Philosopause

Too many of the characters here have entered the phase of their career that has been called "the philosopause." They have retired from the university or grown bored with lab work, and so have taken up professional cogitation.

Source: wiktionary

This term, which is perhaps loosely derived from "menopause," was originally used specifically for neuroscientists, some of whom have tended, as they've grown older, to abandon science-based attempts to map the workings of the brain and have turned instead to more general speculations about the nature of consciousness... The term seems, however, to be taking on a new, broader life, ... in which it is applied to scientists of all stripes.

Source: wiktionary

My own textbooks and review articles, and (after my philosopause, a change of life that afflicts laboratory biologists of a particular age, and makes them write pretentious books that address the Big Questions) my books ... have presented this alternative view, based in observations and generalisations but without the benefit of a rigorous theoretical model.

Source: wiktionary

The current norm of science is that research consists in the publication of peer-reviewed papers in specialist journals. As one nears retirement, it may be acceptable to switch to writing reflective what-does-it-all-mean review papers, and even a book or two: This is known as going through philosopause. Gould went through philosopause early, and Allmon attempts to explain why, connecting the form of Gould’s work as an essayist and book author with his humanism, his liberalism and his interest in exploring murky, large-scale questions.

Source: wiktionary