Today I'm at my country cottage.

When the central heating takes effect I'll get up and make myself some tea and porridge to which I'll add some nuts and fruit. I'll switch on The World Service to hear the news, and then make a few phone calls about damp-proofing. And I'll probably plant the daffodil bulbs for Spring (it says on the packet they should go in now). I think I'll then go to the supermarket and get some things for lunch and dinner, and perhaps take a bus into Norwich to look at getting a new bed. I don't have broadband in the cottage so I'll also check my emails in Norwich—pre-book a train back to London and pay an electricity bill by electronic transfer.

And here's what I won't understand about all this. I won't understand how the oil that drives my central heating got from a distant oilfield to my house. I won't know how it was refined into heating oil or what commercial transactions were involved. I won't know how the burner works. I won't know where my porridge or tea or nuts came from or how they got to me. I won't know how my phone works, or how my digital radio works, or how the news it relays to me was gathered or edited. I also won't understand the complexities of organising a bus or train service and I couldn't mend any of the vehicles involved. I won't really understand how a supermarket chain is run, or how beds are mass-produced, or how wifi works, or exactly what happens when I press "send" on my email or transfer money electronically. And as for running an energy utility company, or putting in damp-proofing, or hybridising daffodils to get these particular varieties, or why exactly I shouldn't plant them later than December…I won't understand any of that either.

Now here's the funny thing. I won't be in the least troubled by my vast ignorance about almost everything I'll be doing this morning. I'm used to it: I've been getting more and more ignorant all my life. I have a huge amount of experience in being ignorant and not worrying about it. In fact, what I call "understanding" turns out to be "managing my ignorance more effectively."

My untroubled attitude results from my almost absolute faith in the reliability of the vast supercomputer I'm permanently plugged into. It was built with the intelligence of thousands of generations of human minds, and they're still working at it now. All that human intelligence remains alive in the form of the supercomputer of tools, theories, technologies, crafts, sciences, disciplines, customs, rituals, rules-of-thumb, arts, systems of belief, superstitions, work-arounds, and observations that we call Global Civilisation.

Global Civilisation is something we humans created, though none of us really know how. It's out of the individual control of any of us—a seething synergy of embodied intelligence that we're all plugged into. None of us understands more than a tiny sliver of it, but by and large we aren't paralysed or terrorised by that fact—we still live in it and make use of it. We feed it problems—such as "I want some porridge" and it miraculously offers us solutions that we don't really understand. What does that remind you of?

I read once that human brains began shrinking about 10 thousand years ago and are now as much as 15% smaller than they were then. This corresponds with the point at which humans stopped having to be multi-competent individuals able to catch their own food and light their own fires and create their own tools and could instead become specialists, part of a larger community of humans who—between them—could do all the things that needed doing. Isn't the vast structure of competences and potentialities thus created indistinguishable from "artificial intelligence"? The type that digital computers make is just a new fractal detail in the big picture, just the latest step. We've been living happily with artificial intelligence for thousands of years.