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Demand decisions based on evidence, not ideology


Psychology can moderate our response to unsavoury actions such as the US ban on immigrants, but we should not let our appetite for dissent diminish.

After police and reservists were called to deal with protests at the 1968 Democratic National Convention in Chicago, Illinois, psychologists who studied reports of the ensuing violence made a curious observation. The officers with firearms seemed more willing than their colleagues without guns to use truncheons and other implements against protestors. It was as if the mere presence of the guns, which they could not use unless they believed lives were in danger, lowered the threshold at which other forms of violence became acceptable to them.

The psychologists attributed this mental shift to the ‘contrast effect’: a common regulator on human perception. The officers knew they were not using the lethal force of their guns, so the use of sticks and electric prods didn’t seem so severe to them. Not as severe, certainly, as it did to the other police without guns, or to the protestors and psychologists.

We see the contrast effect in the optical trick that makes a grey square seem more black or more white depending on the background, and in the lukewarm water that feels scalding hot when your hands are cold. We also see it in the way some media and observers responded over the weekend to the new restrictions on immigration that have been rushed into force by President Donald Trump.

Scientists are among those severely affected by the executive order that blocked entry to the United States for citizens of seven predominantly Muslim countries. As the personal, professional and legal implications of the policy have emerged, the Trump administration has supposedly softened its stance, and, for example, said that US green-card holders will be exempt. Whether by accident or design, the instinctive response to this apparent concession — the mental sigh of relief — draws heavily on the contrast effect. The situation is bad, but not as bad as it could have been. The stick is less severe than the gun.

As the Trump presidency continues and more of the promised policies are introduced, it is important that scientists and others continue to see the stick. The tactic, if indeed it is deliberate, of taking an extreme initial position and then retreating behind a bridgehead, should not mask the likely impact of the commuted action. Normalization is not an option. Equally, it is crucial that there is no decrease in the appetite for dissent and protest over unacceptable and ill-informed decisions that are based on ideology rather than evidence — on vaccine safety and climate change, for example.

Trump has made a bad situation much worse.

Still, scientists should remember that problems and chaos similar to those thrown up by Trump’s immigration ban have been seen and challenged before. In 2003, for example, an editorial in Nature Neuroscience reported how an Australian colleague on the journal was prevented from returning to his New York home for nine weeks after a day trip to Canada, because he was born in Malaysia — a country that was added to a US state department watch list after the terrorist attacks of 11 September 2001 (Nature Neurosci. 6, 203; 2003). (It’s worth remembering also that scientists from Israel cannot enter many Arab nations, and the same restriction can apply to anyone with an Israeli stamp in their passport.)

The crackdown on entry visas for the United States and elsewhere after the 2001 attacks triggered a strong and effective series of protests about the impact on science. The International Council for Science called on the dozens of national academies and scientific societies among its members to hold their conferences outside the United States. The US National Academy of Sciences and others issued warnings about the dependency of the US research system on migrant minds, and how promised visas — and the careers that depended on them — were being cancelled for young scientists from Pakistan and elsewhere. It took years for the promised fixes to the system to be introduced.

Trump has made a bad situation much worse. The acute problems and distress his order has caused to researchers and others could yet be compounded by the chronic effects of related actions. Changes to the Department of State and reports of the United States possibly withdrawing from international organizations and treaties — many of which are scientific — have raised new fears about the role and status of scientific diplomacy in the Trump administration.

As noted, we have been here before. Here is this journal’s opinion on “science and political responsibility” from an editorial published in November 1935 (Nature 136, 733–734; 1935): “The outcome, as is familiar to all, through the repercussion of economic and political factors, has been the intensive cultivation of the national spirit, to which concessions were made at the close of the War in the interests of justice and peace, but which has now become a source of irritation and danger greater than the injustices which it was fostered to remove.”

The contrast with 2017 is not as sharp as we might like.

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Demand decisions based on evidence, not ideology. Nature 542, 5 (2017).

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