When I left school at 16, my head teacher told me I’d never amount to anything. Well, I haven’t saved the world, or become Prime Minister, but I feel I’ve done OK.

The trouble with most teachers is that they know very little about anything but teaching. Many of them are married to people in similar professions. They work in institutions all their lives. Theirs is a narrow world.

They do an invaluable job, mind you. The best teachers can be a positive influence on hundreds of kids, and can inspire them to lifelong achievement. I’m not dissing them – as teachers. But I know very few teachers who have any idea what is entailed in, say, being an airline pilot, or working for an international development charity, or setting up your own business.⁴ Why should they? The best teachers readily acknowledge this.

So most of the time they’re on solid ground teaching you the exam syllabus, and hopefully enthusing you about the subject. But beyond that, don’t take what they say too much to heart. I’ve known children berated endlessly for poor handwriting, for example, without ever being reassured that in most jobs it won’t matter in the least. They’ll be using a computer anyway. We’d all prefer good handwriting, but if it eludes you it doesn’t matter nearly as much as your teachers will make out.

Some teachers bang on about the need to conform. And lots of us don’t have a problem with that. But some people do. If you’re a teacher, it’s true that you do need to conform, as you work in an institution that relies heavily on it. And that’s where some teachers fail to see beyond their own world. The fact is, if you want to be a research scientist, or a graphic designer, or a freelance writer, there will be lots of opportunities for you where your non-conformist outlook will be accepted or even embraced.

So remember that teachers don’t know everything. They know a great deal about their own subject, about learning, about working in a traditional institution, about children. But there are big gaps in their knowledge of the world too. So if you were always told at school that your presentation was rubbish, or that your attitude was wrong, don’t be disheartened. Find yourself a career where they place less value on those things, and more value on the things you’re good at. There’s a career for everyone out there somewhere, whatever your own personal mix of talents and attitudes. Trust yourself, whether you’re still learning or whether you’ve moved on, and play to your strengths.

And if you’ve spent the whole of this Rule thinking it was written just for you, because you’re a non-conformist with rubbish handwriting, take my advice and don’t go into teaching.