When I came to compose this speech, I found myself drawn back to the entry that I had recently written for this year’s Yearbook.

I realise that, at the moment, my thinking is being dominated by the significance of complexity for school and, indeed, for life in general. Last week, I found myself in a meeting with a Professor at Education University of Hong Kong, Mark Mason, who is the editor of the book Complexity Theory and the Philosophy of Education, which I first read maybe ten years ago and which has guided my thoughts about teaching and learning ever since.

Yes, give me half a chance and I’ll bore you on the topic of complexity. And that’s what I am going to do now …

You are about to leave school and I believe that there are a limited number of concepts without a passing understanding of which you are simply not equipped to understand the way the world works. Evolution would be one. Energy another. And complexity a third. There are others, but that will do for now.

To understand complexity, you must understand that complexity is not a synonym for complicated. Yes, both refer to something that has many inter-relating parts, but where a complicated system is predictable, a complex one is not; where a complicated system features linear cause and effect, a complex one has non-linear, disproportionate effects; where in a complicated system the parts add up to the whole, in a complex system the whole is more than the sum of the parts; where in a complicated system what you see is what you get, in a complex system you will be surprised by emergence. A clock is complicated; a cloud is complex. The former measures time with precision; the latter produces rain with caprice.

School, to my mind, is complex, not complicated. Why so? Because the human beings, who make a school what it is, are themselves complex. Irreducibly so. The very moment you conceive of humans as complicated rather than complex, you are doing them a huge, unforgivable injustice. The world of Big Data is not, finally, a fully human world. To understand this, you must understand the difference between a blink and a wink.

Reviewing your careers at school, I believe that you have taken significant steps on your journeys towards embracing complexity, in all its messiness, and eschewing the seductions of complicatedness.  Which is to say, refusing to believe that everything is controllable and simple if you just wish it hard enough.

I believe you are getting better at understanding and working with the unpredictable, capricious, emergent, non-linear reality of humans as they live their lives in a hugely complex but finally wonderful world.

As you leave ICHK, I hope you will leave with this one lesson tucked under your belts and thoroughly internalised. Life is complex, there are no easy solutions, and those that appear simple usually end up making things worse. But with enough subtlety of thought, enough openness of mind, and enough willingness to learn from others, life is a fantastic challenge that brings many joys and rewards.

You are headed now to University – the perfect place to continue to refresh your knowledge of this lesson.

I wish you all every good luck.