If you are interested in the history of
ideas, at some point this question will occur to you: "How is it
possible for someone to gain influence, yet at the same time retain his
independence?" If you traffic in ideas, you have to be able to do both.
I suppose my two favorite recent examples of people who have maintained their independence, but whose ideas have had considerable influence, are Ludwig von Mises and Murray Rothbard. They are more influential today than they were at the time of their deaths. Mises died in 1973. Rothbard died in 1995.
Mises had the great advantage in the final phase of his intellectual career in the fact that Yale University Press published his books from 1944 to 1957. This gave him an audience.