Ideological fixations can lead people to believe what they want to believe

Opinion: If we value truth we may be called on to jettison our most cherished beliefs if the evidence demands

One of the paradoxes of the information age is the all too often vast gulf between what is popularly accepted and what is objectively true. In almost every sphere of human endeavour, misconceptions abound and frequently have a detrimental effect on understanding, debate and decision-making. But does this need to be the case?

This disconnect is well illustrated by a survey commissioned in the UK by the Royal Statistical Society (RSS), which highlighted that as regards emotive social issues, public perception was massively out of sync with the facts. The British public estimated the teenage pregnancy rate to be 15 per cent: the real figure is less than 0.6 per cent, and has fallen for decades. Respondents estimated welfare fraud accounted for 24 per cent of the social welfare bill; the actual figure was 0.7 per cent. People believed a third of those living in the UK were immigrants ( the actual figure is 13 per cent) and that 24 per cent of the population were. Muslims (only 5 per cent are).

A survey conducted in Ireland on behalf of The Irish Times found similar misconceptions – 68 per cent of people believed crime here was increasing, when it has decreased markedly both in Ireland and across the western world year on year.

The Irish also estimated that immigrants made up 25 per cent of the population, rather than the actual figure of 12 per cent. Political issues were also rife with misconceptions. Almost half the country are under the impression that politicians receive the most money from the public purse: in fact social welfare costs are roughly 200 times greater than total Oireachtas costs, with pensioners rather than the unemployed being the single greatest beneficiary.

Political spin
The RSS pointed out three major reasons for this chasm between perception and actuality. The first is political spin. Politicians often distort statistics for their own ends rather than engaging with the numbers honestly.


The second problem is a penchant for shock reporting and provocative headlines. Fair-minded reporting of topics like teen pregnancy, immigration, welfare fraud or crime is not in the interest of the tabloid press. Objective reality often does not instil the desired sense of outrage, or indulge the reader’s sense of moral superiority and inherent biases. Consequently, reality is expunged from the narrative in favour of screaming sensationalism. Sadly, the shrill scandal-mongering of the redtops has a powerful impact on public opinion.

The final point the RSS made is that we are quite statistically innumerate and easily misled. Poor statistical reasoning is rife in both media and public discourse and allows the wool to be pulled over our eyes far too easily.

Evidence, what evidence?
Such problems are in no way unique to Ireland or the UK, with disconnect being even more prominent in politically polarised countries like the United States, where arch-conservatives frequently make highly political claims that are unsupported by of any evidence.

Much of this divergence can be ascribed to confirmation bias, our tendency to acknowledge evidence which agrees with our views and to disregard conflicting evidence.

A study this year by Kahan et al illustrates this. Participants were given a series of statistics problems. When the problem concerned itself with a politically neutral situation, those with good numeracy skills could solve it. When it concerned gun-control laws, subjects fared the same when the conclusion aligned with their political belief, but much worse when it contradicted it, showing that even quantitative information can be distorted by people’s political bias.

Such ideological fixation can lead to attitude polarisation, whereby people become unwilling to adapt their views or consider evidence impartially. The results are invariably bad decision-making, deadlocked attitudes and detrimental consequences for all.

Despite all of this, we live in an age where it is easier than ever to challenge our own misconceptions and those of our peers. Access to sound information is easier than at any other time in history.

If we truly wish to make decisions based on fact and not prejudice, we have to think like scientists and evaluate evidence in a critical and detached manner.

Rather than merely searching for evidence to confirm an idea, scientists try to falsify or disprove their hypothesis. If the theory fails to withstand this process, it is discarded.

The biologist TH Huxley once remarked wryly that the great tragedy of science was "the slaying of a beautiful hypothesis by an ugly fact", but if we truly value signal over noise we must be willing to jettison even the most cherished beliefs if the evidence demands it.

Dr David Robert Grimes (@drg1985) is a science writer and physicist at Oxford University. He blogs at