I have some helpful things to say if you are thinking about taking LSD. Do it somewhere nice. A safe space, if you like. And do it with people you trust. One of the worst days of my life was taking it and going to the Dolphinarium in Brighton. Not one of my most sensible decisions in retrospect (and there is a fair range to choose from). I don’t really like dolphins anyway and there they were, these weird rubberised fish things being sexually taunted by women in wetsuits. I was convinced they would leap out of the water any second, massacring the audience while making those horrible chattering noises. On the train back to Victoria, I was certain we were actually on the way to Auschwitz but no one wanted to admit it. So that was what you might call a bad trip, maan. And I hope this is putting you off taking this drug sufficiently for you not to bother to tell me it is illegal and potentially brain mashing.

Though, obviously, not in my case. I am a fan of psychedelic drugs, although I rarely touch them these days. I am waiting for my retirement – which, after this public service announcement, may come quicker than I had anticipated …

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But to explore one’s consciousness, to feel synaesthesia, to feel a union with all living things, the pulse of the cosmos, why is this such a bad thing? Sure, the copious vomiting involved in the fashionable Ayahuasca ceremonies (why go to the Amazon when you can get a shaman in East Sussex?) is a bit of a bore. But it’s detoxing too, right? If the idea of being out of your mind makes you anxious, clearly none of this is for you. Not even mushrooms. Let’s just stay on the good drugs, from antidepressants to HRT to Ritalin, and behave as if chemicals in themselves have some kind of moral value. Good drugs save lives, bad ones end them and, well, others change them.

Acid can do this and has been used for a number of purposes over the years. While it was associated with the dark side of 60s counterculture, in the early 50s the military were researching its capability as a potential chemical weapon. They found that LSD would render military forces indifferent to their surroundings and it could be used to create confusion and apprehension: what we might call terror. From 1966, it was banned in California and other US states followed. Of course, it resurfaced again in the 90s at raves, its use dropping again by 2000.

But it’s only now that some of the studies about what psychedelics do are being resumed. Now, with the result of much more sophisticated brain imaging, scientists can see some of what is happening and there appears a possibility that these drugs could be helpful for some people. Some people. “Turn on, tune in, drop out” is hardly the spirit du jour. Instead, City boys and students stuff themselves full of smart drugs such as modafinal to pull all nighters.

At Imperial College, researchers have been looking at the effects of psilocybin (the psychedelic component of magic mushrooms) on 20 people with severe depression for whom all other treatments failed. Many showed some improvement. Jamie Bartlett made an interesting programme about the possible therapeutic effects of experiencing a looser form of consciousness; MDMA, after all, was used originally in marriage guidance sessions.

No one doubts that such drugs can have harmful effects but, as with medicinal marijuana, why can’t we just find out if the benefits outweigh the negatives? Some compare the complex visual hallucinations associated with LSD to the undifferentiated nature of the infant mind. This can bring about both self-awareness and wellbeing, which may help certain depressives, addicts and people with OCD. These are small experiments with small numbers of people, but there have long been unofficial reports of MDMA helping those with Parkinson’s. But too many are scared to go there.

Recreational drug users, however, do know – and I am unapologetically libertarian on this issue. It is our choice, not the state’s, whether we want to chemically reduce or expand our consciousness. At a time when mindfulness and every other yoga class promises nirvana, why we are so afraid that we could just reach transcendence through a pill? This seems neither natural nor properly mystical, and so befuddled are our politicians that they have stalled on their lunatic psychoactive substances bill, as even they could not identify drugs that have yet to be invented.

If transcendence is available chemically, organised religion becomes little more than what Aldous Huxley recognised as a system of rites and sacraments and hierarchies. Huxley was less keen on the plebs having access to what Jack Kerouac called “the golden eternity”.

As is clear the world over, in the war on drugs, drugs won. But we still can’t talk about how football violence fell as ecstasy use grew. We still think LSD will make us think we can fly and throw ourselves out of tower blocks. So for me to say that this is a drug that has improved my life, and my understanding of it, considerably does not mean that I think anyone else should do it at all. Being driven through Manhattan on mescaline, though, was … quite good. The point is that to make up your own mind you have to know your own mind. How you get there is entirely up to you.