At eleven, I sat an exam that sorted me into a higher academic tier. The system decided I was bound for university and a professional career: middle class, white collar, a head start.

It didn’t work out that way. Harsh discipline and learning by rote were still considered legitimate teaching methods, and their sole purpose was to get children through exams. Failure was never the school’s fault. It was a personal, moral, intellectual defect in the child.

I was labelled lazy. I was punished physically. I didn’t rebel. I switched off, and escaped as soon as I legally could.

So it’s perhaps not surprising that my view of academic and, to some extent, vocational qualifications is dim, or that I find the idea of needing ‘permission’ before you can operate in any given sphere anathema.

(I do, of course, make an exception for any profession involving the lives and well-being of others. I no more want a self-taught surgeon poking around inside me than you do.)

But I believe we each have the freedom to pursue our interests without first gaining ‘official’ approval. My experiences at school led me to that belief, and I’m grateful. Had I been the academic success they expected, my working life would have been far less varied and interesting.

I hesitate here. I have a strong aversion to blowing my own trumpet. But I’ve stated a belief, and I need to show it was shaped by experience. So here are some of the things I’ve done without any qualifications:

Worked as a motor mechanic.

Helped develop National Standards for the Flooring Industry.

Wrote and published three books.

Built an ocean-going catamaran.

That last one is the source of my greatest pride.

The idea of building a 38ft sailing catamaran, designed to cross oceans, by myself, in a leaky cold barn in the middle of England, seemed ludicrous to everyone I mentioned it to. To be honest, there were times it seemed ludicrous to me too.

I’d never built a boat. I’d never used epoxy resin. I’d never laminated fibreglass.

It took 5,000 hours over seven and a half years. For the first four of those years I worked on her in the evenings and at weekends, after eight to ten-hour days in a tough job. Every spare penny I had went into the build.

Mistakes were made, of course they were. I don’t know if you’ve ever put too much hardener into a plastic pot of epoxy resin. Perhaps my old chemistry teacher taught us about exothermic reactions, I probably wasn’t paying attention. Let’s just say that a plastic pot bursting into flames in one’s hand tends to engrain itself on ones memory.

But you don’t know what skills or knowledge you need until you’re building for real.

Seven and a half years after starting, my catamaran went into the water. She floated.

We sailed her from Falmouth to the Mediterranean. She’s now in Indonesia, having crossed the Atlantic and Pacific oceans.

If you’d told me that on the cold, dark December night in 2006 when I cut the first bits of plywood, I wouldn’t have been surprised. I wasn’t building her to prove anything to anyone.

I was doing it for myself.