Yes, you are right about the jokes, and Amis is withering about people who don't have a sense of humor. For example, the novelist James Buchan--the "humourless worthy": "I don't know if Mr. Buchan is a parent, but I often wonder how the humourless raise their children. How does it get done without humour."
There's also "fuck off." "Fucking" is one thing: "P.S. Dad: I thought your poems were fucking good. Especially 'A.E.H.'. which I know by heart." "P.P.S. On [sic] retrospect I consider 'Middlemarch' to be fucking good--Jane Austen + passion = dimension." But "fuck off" is another: "My father and I had occasion to agree that 'fuck off' was very funny. One naturally admired it's brutality and brevity--but it was also terribly good." Naturally, there's "the best fuck off of all time." Martin Amis:
--What's so funny?
--I saw a bloody fool of a dog just now ...
It was a genuine summer's day, concerted and cloudless. On his walk to the letterbox my father had passed a fullgrown Alsatian apparently asleep on the boiling breast of a parked car. He looked interestedly at the dog and the dog roused itself and stared back, as if to say: I'm lying on this car--all right? On his walk back from the letterbox he looked at the dog again, and the dog stared back, adding: It may be hot but I'm still lying on this car. Before opening the garden door he turned for a final glance.
--What did it do? I urged him, because he was laughing quietly and richly to himself.
It lifted its head from its paws and straightened its neck and went ... Kingsley did one of two things. Either he made the bark sound exactly like fuck off. Or he made fuck off sound exactly like the bark.
If laughter is vital, so are the disagreements. Father and son agree about "fuck off," about Shakespeare ("To say or imply that the man of this name is not our greatest writer marks a second-rate person at best."), and about the last 40 lines of Paradise Lost ("the greatest thing in non-dramatic poetry in English"). But they vehemently disagree about Nabokov, nuclear weapons (Kingsley, writing to a friend, calls Amis a "fucking fool" for supporting nuclear disarmament--he means that Martin should know better), and much else. There's also plenty of confrontation, such as this exchange from the chapter "Failures of Tolerance." Kingsley:
--I've finally worked out why I don't like Americans.
--Because everyone there is either a Jew or a hick
--. . .What's it like being mildly anti-Semitic?
--It's all right.
--No. What's it feel like being mildly anti-Semitic. Describe it.
--What's it feel like? Well. Very mild, as you say. If I'm watching the end of some new arts programme I might notice the Jewish names in the credits and think, Ah, there's another one. Or: Oh I see. There's another one.
--And that's all
--More or less. You just notice them. You wouldn't want anyone to do anything about it. You'd be horrified by that.
Kingsley Amis wasn't an anti-Semite, though what he has to say about "Americans" is revolting. He was not another David Irving, though his enemies liked to portray him as if he were. He was prejudiced, and one his favorite vices was shocking people--in my experience, a familiar tactic of immensely clever, very funny, but essentially shy men who find silence deeply intimidating. Kingsley's remarks are unsettling, yet the important point here is that few things went unarticulated between these two men. Only at the end of Kingsley's life--when there are no more fuck-offs, when all that Kingsley can type are pages and pages of i's and o's and seagulls--does the conversation falter.
You quoted Amis on his father, Andy: "When he made you laugh he sometimes made you laugh--not continuously, but punctually--for the rest of your life." Experience makes that brilliantly clear, I agree, though I'm sure some reviewers will go about their tireless quest to prove the opposite. And there really isn't any answer to these blunt investigations, except, perhaps, "Fuck off."