I can think of at least three reasons why so many people are angry at the Conservative peer Baroness Rawlings, who stood up in the House of Lords this week and suggested people should use electric blankets to keep their energy bills down.

The first reason is inverse snobbery - that most socially acceptable of prejudices. The second is anti-Englishness, which is being exploited by the Yes side in the independence debate. And the third, and most frustrating, reason is our collective lack of common sense.

What Baroness Rawlings said on the subject of electric blankets was this: "They are very green as they use little electricity and they reduce the need for so much heating in the home." In her own home, she said, she uses a blanket and an open fire as much as she can because heating is so expensive and she said that this should form the basis of official government advice. What the baroness's critics said in response, in all the familiar places on the internet, was: how dare a toff lecture us about heating, how dare someone who lives in a big house comment on energy bills, who does she think she is?

Some of this reaction was predictable because Britain is a class-conscious country although most of the class consciousness travels up the way, not down. In other words, we cannot stand a posh person and, even worse, a posh person with an opinion. As many of the baroness's critics pointed out, she lives in a house with many rooms. She also has a seat in the Lords and that's a fact that infuriates and inflames inverse snobs. If there's one thing they cannot abide it's difference, even though the size of Baroness Rawlings' house, or the size of her entry in Debrett's, is irrelevant. What matters is whether she's right or not.

The second reason for all this anger at the baroness - anti-Englishness - is even more unpleasant, but it's an emotion the Yes side often appear willing to exploit. In the case of Baroness Rawlings, they also have the added bonus of that magical combination of concepts the Nationalists find so titillating and horrifying: English and Tory.

However, in suggesting that Baroness Rawlings is out of touch down at Westminster and that her advice is flawed, her critics have the situation the wrong way round. In fact, what the baroness says is consistent with much of the guidance from the NHS and charities concerned with the elderly. Indeed, their advice goes further, with Age UK for example suggesting people should wear hats in bed and wrap blankets round them while sitting down. The only reason people aren't furious about that advice is because it comes from a charity rather than a Tory baroness.

As for the baroness being out of touch, as far as I can see it is her critics who are guilty of that. In fact, not only are they out of touch with basic common sense, they are forgetting the opinions of the one group that talks the most sense: grandmothers.

Take my maternal grandmother, for instance. She was from Caithness, hardly the warmest place in Scotland, but she would have agreed with every word Baroness Rawlings said even though she did not live in a big house or have an entry in Debrett's. What she did have, though, was a sensible, conservative approach to energy and bills. It meant that, although my granny had central heating, she kept it off as much as possible and used one fire and an electric blanket. And if I ever complained that her house was cold, she would give me the response she gave everyone: "Put on another jumper then!"

For some reason, many of us have forgotten the good sense of that approach,which was part of a wider Scottish dislike of waste, and it is probably because gas and electricity used to be reasonably affordable. We have also raised a generation of Scots who like to turn the heating up in December and walk around the house in a T-shirt.

We cannot carry on like that, not least because energy bills will continue to rise, and we also cannot afford to angrily turn on people, such as Baroness Rawlings, when she suggests an alternative. All she said was that we should use as little energy as possible and look at alternatives to having the heating on all the time. That is common sense, whether it comes from a Scottish granny or an English baroness.