How do we let the most trivial setbacks really ruin our day? I only nipped into the Co-op in Cowley Road for two minutes, but when I came back the bike didn’t look right – it looked imbalanced somehow.

The front light was still there but the back one was clean gone. I looked up and down the street incredulously, but there was no one about, certainly nobody who looked as if they had just stolen a bike light. I checked every inch of ground around the racks, checked in my pannier. Nada.

There’s a CCTV camera above the racks, just inside the Co-op’s window. I ran back in (front light in hand) and asked the security guard to show me the footage. No luck. The camera is trained inwards, sensibly surveying the wine and beer section.

I never leave anything nickable on my bikes. My wheels and seat posts all have security skewers, so you need a special allen key to undo them. I only leave panniers or lights on when I leave a bike for the briefest moment.

This time my guard was down, and the two or three minutes I was away was all it took. I wondered how far away the thief was – perhaps watching from a safe distance waiting for me to shove off, waiting for the next hapless cyclist to leave an unsecured item.

The thief was almost certainly not a cyclist because he left the bracket that fixes it to the bike, and the bracket is easy to unscrew by hand. The wretch stole it thinking he’d make a few quid, not realising that without a bracket the light is of no use to anyone.

It was when I got home that I remembered the two reprobates who I’d seen crossing the bottom of Divinity Road, heading for the bright lights and cheap booze of the Co-op.

I was locking the bike to the rack and looked up as one was saying, “I am desperate.” “Me too,” said his mate.

It must have been those ne’er-do-wells who nicked it. They were in and out of the shop a good minute before me. One could have kept watch on the shop exit or tills while the other one did the deed.

Maybe I left the shop too soon for them to snaffle the front light too.

Maybe the front light was harder to detach than the rear, or is too battered to be worth stealing at all.

They wouldn’t realise or care that they’d stolen a Cat Eye 10-LED light worth £34.99. Did I really spend that much on a rear light? I must have been mad. Not half as mad as I am now – not only am I rear-lightless, but I bet the light never gets used. They’d get bored trying to sell it and toss it away in an alleyway, because who’d buy a light from a street drinker, a light with no bracket?

My wife refused to let me go and find them – for I knew exactly where they’d be. They’d be sitting on a bench in Manzil Way quaffing indeterminate liquids from bottles disguised inside plastic bags. My wife pleaded it wasn’t worth it. They’d have mates and they might be carrying, so a direct approach would be crazy.

It’d be easy from a short distance to spot them offering a flashing red object to passers by, but, although I could easily call the police, with no proof the light was mine the incident would come to nothing.

Instead, I logged my loss with a patient operative on Thames Valley’s non-emergency number and spent the evening seething about drink/drug-related petty crime.

I felt a lot better after a few hours’ fantasising about illiberal projects such as forced labour programmes for convicts. I could picture clearly my two thief chums as model workers on a cycle super-highway for the city.