Is anyone serious about the politics of happiness? David Cameron dipped a toe in the water, using the word lightly, but denying the hard policies it implies. Labour shies away from it, but should take up the challenge.

Inequality makes everyone unhappy, the poor most of all, and that is well within the remit of the state. More money gives less extra happiness the richer we get, yet we are addicted to earning and spending more every year.

But the single overwhelming reason why jails are bursting is longer sentences given for more crimes.

My mother begged doctors to end her life. She was beyond the physical ability to swallow enough of the weak morphine pills she had around her. When she knew she was dying I promised to make sure she could go at a time of her choosing, but it was impossible. I couldn't help.

Could a government dare to set out with happiness as its goal? Now that there are accepted scientific proofs, it would be easy to audit the progress of national happiness annually, just as we monitor money and GDP.

Working lives are for the state to influence. Unemployment makes people unhappy. So does instability.

It is now possible to quantify people's levels of happiness pretty accurately by asking them, by observation, and by measuring electrical activity in the brain, in degrees from terrible pain to sublime joy.