Reasonableness is the new right.
In a society with no single set of beliefs defining how we should view right and wrong, those who lead use reasonableness as the benchmark against which everything should be measured.
It's a concept that suits the middle classes who, by and large, know how to do most things without having to resort to screaming and shouting.
They know that people will forgive just about anything provided you are reasonable.
Who, after all, can argue with those who are reasonable? Such people avoid giving offence. They speak slowly but are not over-confident. They give their interlocutors time to speak. They show that they listen. And having listened, they show that they are don't intend to get their own way. Meeting people half way is reasonable.
Politicians use reasonableness to easily win arguments. For example, in recent months, local authority chief executives have been criticised for the size of their salaries. Their wage packets have been compared to that of the Prime Minister. Perhaps not unreasonably, a question has been implied: is it reasonable that a council chief executive should earn more than the PM? Most reasonable people would say not.
So the case is made. And woe betide anyone bold enough to say that their job is more complex than Mr. Cameron's.
The advantage of being reasonable in PR terms is that it's tabloid ready. The red tops are founded upon faux reasonableness. We've all seen the stories: People who are on benefits taking home more than people who are working more than 40 hours a week. An outrage - most reasonable people would say. Public servants with their gold-plated pensions: surely they should have less than the private sector who work for a living? You could write the stories in the shower.
So along come the riots - utterly unreasonable behaviour by any standard. But the response to it must also be reasonable. And there is the challenge - how to pitch the response so that most people think politicians' reaction is not over the top. It's not an easy thing to pitch, not least because different groups have different standards for reasonableness.
There will be those who believe that where our peace of mind and sense of security is threatened the perpetrators must be dealt with brutally and swiftly. No mercy. Prison sentences. Throwing people out of council houses. And the rest.
But others - maybe reasonable people too - will say that such a response is excessive. After all, people get caught up in the prevailing mood. Where there are crowds, noise and adrenaline, sheep will follow sheep.
Reasonable people know that not everyone is a violent iconoclast determined to wreck our society.
Some suggest punishment; others understanding, analysis and not acting with undue haste.
The trouble with reasonableness is that deploying it as a neutering weapon can render debate useless. Sometimes we need to dig deeper.
The impact of accusing people of being unreasonable can be perverse. Look at those people who are paid from the public purse - TV stars, public agency chief executives, doctors, nurses, teachers. They face some major personal challenges: eroding salaries, paying more for pensions.
It's all to easy to adopt a reasonable position - such people are paid out of taxes so they should expect less than those whose lot is paid by the private sector.
Seems perfectly reasonable. No?
What about the net impact when we can no longer recruit high calibre public servants, when schools struggle to find good teachers, when public services start to fail and endanger lives? It might be reasonable to say that talented people who make a massive difference to public life should be rewarded.
Are council chief executives worth more than bankers? D'oh!
If we assume that the concept of reasonableness has pervaded our society over time then most people will in time use it to judge our leaders - and their responses to crises. And we see such a debate being played out now over sentencing of rioters. What is a reasonable response to those who threaten our liberty? The risk here is that those who would disrupt, or feel that they've got a rotten lot, may feel that they are being over-punished.
This could prompt would-be rioters to feel indignation, even anger, and in time precipitate further social problems.
We should be wary of reasonableness. As adults, we may spend a good deal of our lives avoiding the embarrassment of unreasonable behaviour - people shouting, speaking too loud, becoming physical. We surround ourselves with those who are like us. We frown on those who dissent.
But polite though that may be, such an outlook could be deemed utterly unreasonable since it can result in closing down debate and neutering those who have, like us, a legitimate right to be heard and acknowledged.
I suspect most reasonable people would agree.