ELECTIONS are a wonderful time for those of us who enjoy arguments — not of the quarrel variety, but structured cases made for or against some assertion. Why should you support a policy or prefer one party to another? Those who seek your vote must make their cases. We are about to enjoy a four-week festival of argumentation.

Alas, most of the arguments will involve grave logical errors. Yet the fallacies will not always be obvious. Politicians are skilled dissemblers, especially when they are unaware of their own mistakes. So, over the course of the campaign I will be writing occasional columns on this page aimed at exposing the candidates’ various crimes against logic.

Tony Blair began the campaign with a common offence. In his speech announcing the election date, he claimed that under a Labour government the NHS would be “fair and equal”. To see what is wrong with this apparently innocuous claim, suppose he had instead said that under Labour all NHS buildings would be painted orange.

Everyone would know precisely what Mr Blair was proposing and after the election we would know if he had implemented his policy. But, apart from some hippies and a certain telecoms company, few would support the policy. Which makes it exactly the wrong kind of statement to make.

Politicians prefer statements whose meaning is entirely unclear but which will win everyone’s agreement. Different people mean different things by “fair” but, whatever they mean, they approve of it. Everyone wants the NHS to be fair, whatever they think that means.

“Fair” is a hooray word: of uncertain meaning but guaranteed to deliver cheers of support. It is not the only hooray word. There are also “equality”, “justice”, “progress” and “common sense”. Politicians use such words relentlessly but what they mean by them no one can say.

Politicians could explain what they mean by such words. Mr Blair could tell us, for example, whether he thinks it fair that everyone should experience the same outcome, as some of his comments imply, or fair that people receive what they merit, as other remarks suggest. But he will not. Clarifying his meaning would only destroy the word’s magical power to win agreement. Politicians seek not our comprehension but our votes.

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