Sometimes, I wonder how the human race has risen to the top of the evolutionary pile when almost every single decision we ever make is bonkers. You do not see blackbirds smoking cigarettes or beavers riding motorcycles. You don’t see pigeons ignoring non-organic seeds or bison at the shops buying something they know they can’t afford. You do, of course, see elephants on unicycles, but only because we think it is funny.

Let’s look at the simple decisions I’ve made today. First of all, I hit the snooze button on the alarm clock even though I knew full well that I had to get up and go to work or I wouldn’t be finished till midnight. Then I went downstairs and had a cup of coffee, which I know will make my teeth all brown. And then I read The Guardian, which always makes me angry.

And then, instead of going to work, I put my new cabinet for drinks and guns in the back of the Range Rover. It’s an exquisite piece of furniture, this: hand-made in Yorkshire from American walnut, with brushed aluminium handles, it takes 16 shot glasses and 16 flutes, and there are cutaway compartments for champagne, sloe gin, soup, whisky, 500 cartridges and two Beretta shotguns.

I will use it probably twice a year and the rest of the time it will render the car bootless and consequently unable to take dogs, wellies or even light shopping. So it’s mad. So’s my new quad bike. And so is everything I’ve ever bought. I look at all the things on my desk and I wonder: what on earth was going on in my head when I chose them? The paperweight with the globe inside, the catapult, the Bugatti Veyron cufflinks, the Insanity chilli sauce and the Sony Rolly, which so far as I can tell is specifically designed to do absolutely nothing at all.

I must have said to someone in a shop, “What does this do?”, and he must have said, “Absolutely nothing at all”, and then I must have said, “Oh good. Here’s my credit card.” How mad’s that?

What makes this state of affairs so alarming is that stupidity isn’t simply restricted to the dull masses. Those in power can’t make a sensible decision either.

You have had very senior politicians standing up and telling us that they know Iraq has weapons of mass destruction. And now you have Bob Ainsworth, who has deliberately chosen to grow that moustache.

You may remember a few years ago when Britain’s transport secretary was very fat and had no 11-plus. He made the mistake of digging up the outside lane of the M4 and turning it into a bus lane. This made not just him but the whole government a laughing stock, so you’d imagine no one would make the same mistake again ...

But they have. Only more so. For the past two years my journeys to and from London have been fraught by roadworks near where the A40 crosses the North Circular. It’s been hell and has wasted many hours of my life. But I figured it would be worthwhile because, plainly, those in charge had decided to widen the road.

They have, too. But, amazingly, the new lanes — in both directions — are for bicycles only. I am not making this up. All that time. All that expense. And all for the benefit of a few idiots who can’t afford a car.

To make matters worse, no provision is made for bicycles at either end of the new lanes. It’s highway, then bike lane, then highway. So you can’t try them out without being killed on the way.

When you look at something like this you stop wondering how the human being has climbed to the top of the evolutionary pile. And wonder instead how it’s survived at all. Bicycle lanes on the main road from Oxford to London. Whoever came up with that sits on the Darwinian waterfall of change alongside the housefly. Seriously, my dishwasher has a bigger brain.

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