POLITICS is an adversarial business.

The cut and thrust of debate and the holding of governments to account is a cornerstone of our democratic system, and rightly so.

So blaming our opposition parties for opposing would be rather like blaming fish for swimming. It is what they do; it is what they must do.

But at Holyrood at present, the opposition seem to be swimming in ever-decreasing circles.

Instead of using their privileged position to act in the people's interests by informing them of the issues ahead as we approach the independence referendum, they have chosen to swarm around Alex Salmond like piranha in the hope of nipping off bits of his support.

Point-scoring, posturing and name-calling have become the order of the day. Puffed up with faux indignation, MSPs call for resignations as casually as they call taxis.

The debate on what those same MSPs tell us is the most important political choice of the last 300 years is being obscured, or even lost.

This issue is too important for that to continue.

People look to their politicians for information. What they are getting is virtually white noise.

We have asked before for a reasoned debate on this subject. At the time, it did not seem much to ask.

Voters need information on which to vote. They want to know if independence will result in the kind of country they desire for themselves, their families and society, or whether remaining in the United Kingdom would achieve that. They want to hear and weigh the options. That is not all they want to know, of course.

If ministers have fallen down on the job, if public services are being cut, or if Parliament has been misled, we should all be told.

But a shrieking commentary on the travails of the SNP Government is not the independence debate.

Rather, it is blocking the independence debate by filling up airtime and headlines with chaff.

If MSPs continue in this fashion, other voices may well supplant them. As we report today, the trades union movement is taking a serious interest in what becomes of Scotland and the rest of the UK in 2014. It is treating its membership like adults.

There was another example from outside the mainstream parties in Glasgow yesterday at the Radical Independence Conference.

While much of the left-wing rhetoric was familiar and easy to caricature, there was a genuine desire to articulate a vision of what independence might hold. There has not been much vision at Holyrood of late, just blinkers.

If MSPs cannot rise above the current level of debate, we must hope the debate rises above them.