When weighing up the merits of a product or dangers of a technology we often

In a second experiment, Slovic and Alhakami had students of the University of Oregon rate the risks and benefits of a technology (different trials used nuclear power, natural gas, and food preservatives). Then they were asked to read a few paragraphs describing some of the benefits of the technology. Finally, they were asked again to rate the risks and benefits of the technology. Not surprisingly, the positive information they read raised students’ ratings of the technology’s benefits in about one-half of the cases. But most of those who raised their estimate of the technology’s benefits also lowered their estimate of the risk - even though they had not read a word about the risk. Later trials in which only risks were discussed had the same effect but in reverse: People who raised their estimate of the technology’s risks in response to the information about risk also lowered their estimate of its benefit.

We want useful things to be safe and dangerous things to be useless. Reality has failed to read the branding guidelines. Tell people more about a technology’s benefits; its risks can seem to fall, despite no new risk evidence. Describe the hazards and the benefits shrink by association. One warm or cold feeling has been allowed to mark two separate exam papers.

A beautiful software demonstration can lend imaginary competence to security. Excitement about an electric vehicle can blur the trade-offs around production. Disgust at preservatives can reduce the benefits people are willing to acknowledge. The original judgement may be right. It has simply picked up a travelling companion and started sharing its homework.

“Balanced discussion” solves nothing if every dimension is boiled in one emotional soup. Write the benefit case while leaving risk scores untouched. Assess probability and severity without adjusting usefulness to make the story neater. Only then combine the answers and decide what trade-off is acceptable.

This feels untidy because a technology may remain highly beneficial and genuinely dangerous. Good. Reality is under no obligation to fit on a traffic-light slide.

Keep the scores separate and record why each moved. When excitement rises after a strong demo, the risk number stays where the risk evidence left it. Otherwise the demo has not informed the risk review. It has pickpocketed it.