The other night in a dream I saw my father, who died 11 years ago. He was very clear, recently shaved, with his hair combed and in full colour. He was perhaps 60, although he was 81 when he died. Smiling, he hugged the person beside me (I don’t know who that was), and then he hugged me. I enjoyed the hug. Did this mean anything? Do our dreams mean anything?

I’m fascinated that we don’t know the meaning of something we all experience. I often ask people what they make of dreams. The morning after the dream of my father, I had breakfast in Dhaka opposite an Argentinian scientist. I asked her if she believed that dreams had meaning.

“Of course. I have to, my husband is a psychoanalyst.”

But Francis Crick—of Crick and Watson fame—believes that dreams are just the computer resetting itself as we sleep, and perhaps the function of sleep is to give time for that resetting.

A major division in the world is between those who believe dreams have meaning and those who don’t.

Did my father appear to me because I needed comfort? I was under stress, but that was nothing unusual—and I hadn’t dreamt of my father for years. Or had a neurone that carried an image of my father simply misfired?

I once, when a student, kept a dream diary. As I wrote the entries I was never quite sure how much I was giving form to “stories” that lacked form. My first entry described me walking through a burgeoning tropical garden with masses of rich, colourful blooms, and sweet perfumes filling the hot humid air. Suddenly a black snake appeared and began to chase me. It didn’t slither, rather it took the form of a cartoon Loch Ness monster, going up and down vertically. I ran. It came closer, until suddenly I awoke.

Did this dream have meaning? Friends said it was a “classic Freudian dream,” I was running away from my sexuality, which scared me.

If I write late at night, as I rarely do now, but often did when I had to write my “Editor’s Choice” on a Monday night, the words would usually reverberate through my dreams all night, in a way that was mildly disturbing. This suggests to me the computer resetting itself.

But I do often write talks and articles in my sleep. Ideas come to me. Sometimes they are silly ideas, but some of the ideas make it into the final product. Friedrich August Kekulé said that he dreamt the structure of the benzene ring in two dreams not one, with the second dream featuring a snake eating its tail. That image, the ouroboros, has had great mystical significance for the Ancient Egyptians, Hindus, and others, raising the possibility, advocated by Carl Jung, that psychic archetypes speak to us in our dreams.

Some highly intelligent friends are convinced not only that their dreams have meaning, but they are a source of advice on what to do in their lives. I remain sceptical, and that is, I believe, what most of us think. How many GPs ask patients about their dreams? Not many, if any at all, and most of us would be shocked if they did.

We enjoy to play with dreams as we do with horoscopes, but we don’t behave as if they had meaning. In truth, we’ll never know. We live our short lives ignorant of almost everything important, including whether there is a God and an afterlife and whether dreams, which we have every night, mean anything.

Competing interest: RS dreams but rarely remembers them.

Richard Smith was the editor of The BMJ until 2004. He is now chair of the board of trustees of icddr,b [formerly International Centre for Diarrhoeal Disease Research, Bangladesh], and chair of the board of Patients Know Best. He is also a trustee of C3 Collaborating for Health.