BBC Radio 2’s afternoon programme includes a selection of daily “factoids,” one sentence facts or statistics that might make one ponder.Yesterday’s list included, “people who eat slowly are 42% less likely to be obese.” It was an impressive sounding statistic, but what does it mean? 42% less likely than people who eat at average speed? 42% less likely than people who eat quickly? And what does “slowly” mean? A half an hour to eat dinner? Ten minutes to eat it? As one who eats very quickly, and who carries a stone too many, I have no doubt that the statistic rests on firm empirical research, but the figure by itself lacks a context that would allow it to be interrogated.

Plucking individual numbers from data and presenting them as representative has long been the tactic of governments. In Ireland, the years of the Celtic Tiger economy allowed extraordinary claims to be made, including that Ireland ranked among the richest nations in the world. Anyone who experienced the health service or worked in under-funded schools would have had serious doubts, but politicians would take the national income and divide it by the small population and tell everyone how rich they were. It was easy to produce a very high average personal income by aggregating the income figures and dividing by the total number of people working. Of course, the outliers, the people earning huge amounts of money, caused a distortion of the average. Even now, when statistics suggest a mean annual fee income of €36,000 p.a, the median figure is €26,000 – the average earner is likely to earn €10,000 a year less than what might be presented as a factoid figure.

Factoids might be fun as afternoon entertainment, but are not the stuff on which one would wish to base important decisions. If Irish government statistics, based on a population of 4.5 million, could significantly misrepresent reality, then the potential for such misrepresentation in the United Kingdom is correspondingly a dozen times greater.

The Brexit debate has caused a polarisation of opinion in which every number has become politicised. The Treasury would always have been considered conservative with a small “c” by those on the Left, being perceived as a defender of the political and economic establishment. Now those who are Conservative with a large “c” have politicised an institution they would previously have regarded as neutral and as being above party politics. The Treasury has been accused of producing statistics unfavourable to those advocating a definitive departure from Europe. Instead of firm, empirical evidence, factoids are now quoted by politicians, speculative numbers, when none of them can present a vision of the future that is coherent.

The suggestion that I am overweight because I eat too quickly is a piece of precise science compared with the current discourse.