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

Thresholds of pain, indignity and incapacity are entirely personal.

So what really works? Treatments in jail do some good, but it's mostly too late: finding a family and a job or just growing older make most prisoners eventually give up crime.

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.

Nothing keeps people together like the exalted conviction that they alone are to be spared that eternal anguish of hell fire to which everyone else will be condemned.

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

But how odd that in this heathen nation of empty pews, where churches' bare, ruined choirs are converted into luxury loft living, a Labour government - yes, a Labour government - is deliberately creating a huge expansion of faith schools.