Practical reason is demanding

Quo' Velleman, once in the main text and once in a footnote:

Practical reason thus encourages me to identify kinds of joke, recognizable by family resemblance if not by description, that constitute what is amusing for me.

Yet I am also under rational pressure to identify kinds of jokes that regularly tend to amuse me by themselves [sc. as opposed by dint of my being drunk, nervous, high, or the like], so that I can comprehend my responses to jokes more generally, without reference to the circumstances.

Really?  Rational pressure? I actually am interested in thinking about what sorts of jokes regularly tend to amuse me, at least in a de re sort of way about some of them.  Mostly puns and shaggy dog stories. But that's because I find them interesting, not because I care particularly much about finding out about my responses to them as such, and I'm pretty sure this is a dispensable feature of my character, and not a response to a rational pressure or the dictates of practical reason.