He wished he'd written him last night, instead of joining the usual beer and bull session in the wardroom.
In bull session debate he was instantly beyond the depth of everyone else.
Well, in any event, he evidenced no interest in the bull session, as you described it?
A discussion, esp one among good companions passing time idly but investigating important topics
[1920+ College students; perhaps influenced by bull, ''discuss, visit another student to pass the time,'' attested as college slang by 1850]