Every time I complete a piece of writing, I have three reactions: First, a sense of liberation and elation; then a feeling of sadness that I have nothing to do; and finally a fear that I will never write anything again. I felt all three of these emotions for the first time in 1957, when I completed my doctoral dissertation, and have experienced them again every time I have finished writing a book or a serious essay. You would think I would stop worrying, after fifty-four years, but sure enough, the completion of the "Introduction to the Critique of Pure Reason" produced the same reaction.
One reader wrote an email suggesting that I tackle Kant's ethical theory. Independently, I was thinking about a short introduction to the thought of David Hume. But perhaps I ought to take a few days to think about it before launching into another thirty thousand word undertaking. Once the Dodgers left Brooklyn, baseball lost its attractions, and I never really got the Red Sox, for all that I once rode in the same parlor car as Ted Williams.
Maybe retirement was not such a good idea. Sigh.