I don't imagine there are many people listening to me now who go back to the days when, in Britain at any rate, the phrase LSD was the normal slang phrase for pounds, shillings and pence.

Long after I'd left England it meant that to me, and lay there, buried in my unconscious until one fine cloudless morning, around Christmas time, it must have been 1959 I was taking a slow walk in the Hollywood Hills with a man I'd been sent out to California to interview. He had a very soft, gentle, English voice and he was a scholarly type, not accustomed I fancy to much use of slang. Suddenly he used the phrase LSD and, before I could say what has money to do with it he spelled it out. Not pounds shillings and pence. But something I'd never heard of. Lysergic acid. He was, to come to the point, a man I find you have to identify and describe for anyone under 40. Long a famous novelist and essayist, the reigning highbrow in fact of the 1920s and on into the 30s, he was Aldous Huxley, and after he tickled my unconscious with that odd word, I listened a little more attentively.

Huxley had had bad eyesight since birth. But he was, by that time, and he must have been in his middle 60s, practically blind. That's why it was a slow walk. He had a stick and I took the other arm, but he didn't need to be guided. He knew the hills very well indeed and he tapped his way around most days. Huxley had a remarkably patient and penetrating mind. More precise and better, I now think, as a scientist's mind than that of a novelist. And I now realised that he was reciting various theories about eyesight. What he was saying now was that this acid he called LSD, had not so much improved his eyesight as endowed him with a new dazzling poetic view of everything he barely saw in nature: the bark of trees, flower petals. With lysergic acid, he said, every stone or tiny piece of gravel comes to look like a separate and marvellous jewel.

I found this fascinating and, at the same time, I was uneasy. I wondered whether this drug did quicken and improve the sense that he'd almost lost. Or whether it did truly replace the loss with a vision. It didn't cross my mind then that he did, indeed, see visions. In the succeeding months, I was to learn that Aldous Huxley was not a lone researcher in a psychological experiment. An eccentric Professor at Harvard, name of Timothy Leary, had worked on the stuff too. And within the year, we heard that it was the drug of choice among college youth who had moved on usually from marijuana. And there came a day when the director of the Food and Drug Administration sent a letter to the presidents and deans, principals of science departments, of many colleges and universities. It warned that LSD was an exceedingly dangerous drug which can induce mental aberrations that might be brief or last for days, that it can do permanent damage to the nervous system.

Well, by the early 1960s, lots and lots of college students, and others, had experimented with the stuff. And there were enough of them who, unfortunately, had not experienced anything so dire as the food and drug boys had warned about. But what I realised at the time I was deploring was the usual target of the old – though I was a spry 51 – rebellious youth. Then I thought of how my parents lamented, while loving us deeply of course, a fact we never appreciated at the time, how they lamented our, what we called, emancipation. Every other generation declares itself liberated, emancipated, freed from the constricting, stuffy, and all together wearisome conventions of their parents.

I suppose this has been going on since the beginning of time. A natural war between, especially, fathers and sons. I believe it was Cain, who first said to Abel: "I don't know what she sees in him." Well, let's be serious. We wore trousers that had to be 20/22 inches at the turn-up, Oxford bags. "Well," said my ever tolerant father "I should feel silly." We danced to quite new music invented in America, to the sinister writhing sounds of a revived old instrument, the saxophone. When we got married, we slept in twin, single beds – appalling, my mother thought – we did preposterous dances like the Charleston.

In this country, all alcoholic liquor was banned from the early 20s on. With the result that the young, the very young, couldn't wait to get at the stuff. And carried flasks of bathtub manufactured gin.

But then, after a while, another reflex sets in with the parents, which is: "Well, we may have been wild and silly, but we did not blow our minds on drugs." Which is true. And through the 1960s, the rebellion, which followed the normal course of being liberated from the habits and mores of the parents, was intensified. Grew uglier in a civic sense. When it became clear, and I must say first to the students, that those military advisors that John Kennedy had sent into Vietnam, turned it to fighting Americans, to the tune of half a million. Even General MacArthur and General Eisenhower thought that the suppression of communism in the former French colony was no good reason for America to get involved in a land war in remote Asia.

I suppose it's never been settled whether the young had this good, strategical reason in mind, or whether they were that generation which comes along about twice in a century, that has, at heart, the idea that war, all war, is wicked and useless. This is usually felt and proclaimed by a generation that has just been saved from conquest or persecution by the military mettle of their fathers. Whatever the motive, it was strong and caused a rumpus throughout the land.

Linked unhappily with the moral rebellion, it led to a lot of campus rebellion and a lot of checking out of regular society and into communes and into the flower people. And then, to the much flaunted fatuous slogan, "make love not war." And if the young needed a founding father for their rebellion, he was right there in Harvard. Or he'd just been fired from Harvard. For converting its psychology department into a laboratory for the consumption of mescaline, hallucinatory mushrooms, lysergic acid, the lot. He declared himself the founder of a "League of Spiritual Discovery" which led to many weird and barmy variations. All of whose disciples were all too ready to adopt his required ritual, smoke marijuana for an hour every day and give over Sundays exclusively to LSD. How many students Dr. Leary merely entertained and how many he emotionally and physically wrecked will never be known. Anyway, Harvard had had enough of him and fired him. Made him a martyr to the young throughout the country. And legions of students, especially failing students, adopted his slogan: "Turn on! Tune in! Drop out!"

Well, Timothy Leary died this week. The leader of this retreat into boozy oblivion, that we dignified with the name of the counterculture. Violating the old rule of saying nothing bad about the dead, I'm sorry to say he was the role model for a bad movement. Leary's death has stimulated lots of retrospective, deep thoughts about the 1960s. Most commentators think it was an extreme and sorry time. Some people think it has left a permanent stigma and is responsible for the spread of drugs, illegitimacy, crime, the anarchy of the young.

A columnist in the New York Times, on the other hand, looks back to his days at Harvard. He's proud to be an early recruit to the counterculture and defends it on the interesting and true ground that whereas in his day, his year, his class was 93 per cent white. The class of 1996 is 63 per cent white, 20 per cent Asian-American, 10 per cent black, seven per cent Hispanic. Good. Fine. And even though 99.9 per cent of American children do not go to Harvard, that new ratio of whites, blacks, Asians, Hispanics is I think a fair enough reflection, of a fact: that this is never again to be the white continent. That America is, for better or worse, a polyglot nation.

I have to say there is one good thing that to me came out of the 1960s which I've not seen greatly praised. It is the habit, now quite respectable, of young men and women living together without being married. In the 1920s a judge, one Judge Ben Lindsey, from Denver, Colorado I believe, he said that the best counter move against the new sexual freedom – not by the way very widespread – was something he called, "companionate marriage". Instead of falling in love, getting engaged and soon married, people should try a rehearsal or experimental partnership. See how they got along together and then decide to marry or not. This would save, he thought, a great deal of grief.

This proposal scandalised the whole nation. And Judge Lindsey became a pariah, a byword for the devil incarnate. The hullabaloo over him died down as his idea died down and I suspect was enthusiastically adopted by many of the young. But it had to be still in secret. It was still a social and moral outrage. In time and I don't know how and where, the idea of companionate marriage became the regular thing. And accepted, often ruefully, by the parents.

I have no other retrospective thoughts about the 60s that are cheerful or wise. I've looked back and seen that on 3rd January 1970 I wrote a piece for my paper reviewing America through that past decade. Just as we used to talk about the roaring 20s and the anxious 30s, I thought I'd found the proper label for the 60s. I called the piece, "The Ghastly 60s." So they were. And at another time, I may want to enlarge on how and why.

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