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“My-side bias” makes it difficult for us to see the logic in arguments we disagree with
"Our results show why debates about controversial issues often seem so futile," the researchers said.

In what feels like an increasingly polarised world, trying to convince the "other side" to see things differently often feels futile. Psychology has done a great job outlining some of the reasons why, including showing that, regardless of political leanings, most people are highly motivated to protect their existing views.
However a problem with some of this research is that it is very difficult to concoct opposing real-life arguments of equal validity, so as to make a fair comparison of people's treatment of arguments they agree and disagree with.
To get around this problem, an elegant new paper in the Journal of Cognitive Psychology has tested people's ability to assess the logic of formal arguments (syllogisms) structured in the exact same way, but that featured wording that either confirmed or contradicted their existing views on abortion. The results provide a striking demonstration of how our powers of reasoning are corrupted by our prior attitudes.
Vladimíra Čavojová at the Slovak Academy of Sciences and her colleagues recruited 387 participants in Slovakia and Poland, mostly university students. The researchers first assessed the students' views on abortion (a highly topical and contentious issue in both countries), then they presented them with 36 syllogisms – these are formal logical arguments that come in the form of three statements (see examples, below).
The participants' challenge was to determine whether the third statement of each syllogism followed logically from the first two, always assuming that those initial two premises were true. This was a test of pure logical reasoning – to succeed at the task, one only needs to assess the logic, putting aside one's prior knowledge or beliefs (to reinforce that this was a test of logic, the participants were instructed to always treat the first two premises of each syllogism as true).
Crucially, while some of the syllogisms were neutral, others featured a final statement germane to the abortion debate, either on the side of pro-life or pro-choice (but remember this was irrelevant to the logical consistency of the syllogisms).
Čavojová and her team found that the participants' existing attitudes to abortion interfered with their powers of logical reasoning – the size of this effect was modest but statistically significant.
Mainly the participants had trouble accepting as logical those valid syllogisms that contradicted their existing beliefs, and similarly they found it difficult to reject as illogical those invalid syllogisms that conformed with their beliefs. This seemed to be particularly the case for participants with more pro-life attitudes. What's more, this "my-side bias" was actually greater among participants with prior experience or training in logic (the researchers aren't sure why, but perhaps prior training in logic gave participants even greater confidence to accept syllogisms that supported their current views – whatever the reason, it shows again what a challenge it is for people to think objectively).
"Our results show why debates about controversial issues often seem so futile," the researchers said. "Our values can blind us to acknowledging the same logic in our opponent's arguments if the values underlying these arguments offend our own."
This is just the latest study that illustrates the difficulty we have in assessing evidence and arguments objectively. Related research that we've covered recently has also shown that: our brains treat opinions we agree with as facts; that many of us over-estimate our knowledge; how we're biased to see our own theories as accurate; and that when the facts appear to contradict our beliefs, well then we turn to unfalsifiable arguments. These findings and others show that thinking objectively does not come easily to most people.
—My point is valid, yours is not: myside bias in reasoning about abortion
Christian Jarrett (@Psych_Writer) is Editor of BPS Research Digest
This article was originally published on BPS Research Digest. Read the original article.
Weird science shows unseemly way beetles escape after being eaten
Certain water beetles can escape from frogs after being consumed.
R. attenuata escaping from a black-spotted pond frog.
- A Japanese scientist shows that some beetles can wiggle out of frog's butts after being eaten whole.
- The research suggests the beetle can get out in as little as 7 minutes.
- Most of the beetles swallowed in the experiment survived with no complications after being excreted.
In what is perhaps one of the weirdest experiments ever that comes from the category of "why did anyone need to know this?" scientists have proven that the Regimbartia attenuata beetle can climb out of a frog's butt after being eaten.
The research was carried out by Kobe University ecologist Shinji Sugiura. His team found that the majority of beetles swallowed by black-spotted pond frogs (Pelophylax nigromaculatus) used in their experiment managed to escape about 6 hours after and were perfectly fine.
"Here, I report active escape of the aquatic beetle R. attenuata from the vents of five frog species via the digestive tract," writes Sugiura in a new paper, adding "although adult beetles were easily eaten by frogs, 90 percent of swallowed beetles were excreted within six hours after being eaten and, surprisingly, were still alive."
One bug even got out in as little as 7 minutes.
Sugiura also tried putting wax on the legs of some of the beetles, preventing them from moving. These ones were not able to make it out alive, taking from 38 to 150 hours to be digested.
Naturally, as anyone would upon encountering such a story, you're wondering where's the video. Thankfully, the scientists recorded the proceedings:
The Regimbartia attenuata beetle can be found in the tropics, especially as pests in fish hatcheries. It's not the only kind of creature that can survive being swallowed. A recent study showed that snake eels are able to burrow out of the stomachs of fish using their sharp tails, only to become stuck, die, and be mummified in the gut cavity. Scientists are calling the beetle's ability the first documented "active prey escape." Usually, such travelers through the digestive tract have particular adaptations that make it possible for them to withstand extreme pH and lack of oxygen. The researchers think the beetle's trick is in inducing the frog to open a so-called "vent" controlled by the sphincter muscle.
"Individuals were always excreted head first from the frog vent, suggesting that R. attenuata stimulates the hind gut, urging the frog to defecate," explains Sugiura.
For more information, check out the study published in Current Biology.
Stressed-out mothers are twice as likely to give birth to a girl
New research from the University of Granada found that stress could help determine sex.
Stress in the modern world is generally viewed as a hindrance to a healthy life.
Indeed, excess stress is associated with numerous problems, including cardiovascular disease, high blood pressure, insomnia, depression, obesity, and other conditions. While the physiological mechanisms associated with stress can be beneficial, as Kelly McGonigal points out in The Upside of Stress, the modern wellness industry is built on the foundation of stress relief.
The effects of stress on pregnant mothers is another longstanding area of research. For example, what potential negative effects do elevated levels of cortisol, epinephrine, and norepinephrine have on fetal development?
A new study, published in the Journal of Developmental Origins of Health and Disease, investigated a very specific aspect of stress on fetuses: does it affect sex? Their findings reveal that women with elevated stress are twice as likely to give birth to a girl.
For this research, the University of Granada scientists recorded the stress levels of 108 women before, during, and after conception. By testing cortisol concentration in their hair and subjecting the women to a variety of psychological tests, the researchers discovered that stress indeed influences sex. Specifically, stress made women twice as likely to deliver a baby girl.
The team points out that their research is consistent with other research that used saliva to show that stress resulted in a decreased likelihood of delivering a boy.
Maria Isabel Peralta RamírezPhoto courtesy of University of Granada
Lead author María Isabel Peralta Ramírez, a researcher at the UGR's Department of Personality, Evaluation and Psychological Treatment, says that prior research focused on stress levels leading up to and after birth. She was interested in stress's impact leading up to conception. She says:
"Specifically, our research group has shown in numerous publications how psychological stress in the mother generates a greater number of psychopathological symptoms during pregnancy: postpartum depression, a greater likelihood of assisted delivery, an increase in the time taken for lactation to commence (lactogenesis), or inferior neurodevelopment of the baby six months after birth."
While no conclusive evidence has been rendered, the research team believes that activation of the mother's endogenous stress system during conception sets the concentration of sex hormones that will be carried throughout development. As the team writes, "there is evidence that testosterone functions as a mechanism when determining the baby's sex, since the greater the prenatal stress levels, the higher the levels of female testosterone." Levels of paternal stress were not factored into this research.
Previous studies show that sperm carrying an X chromosome are better equipped to reach the egg under adverse conditions than sperm carrying the Y chromosome. Y fetuses also mature slowly and are more likely to produce complications than X fetuses. Peralta also noted that there might be more aborted male fetuses during times of early maternal stress, which would favor more girls being born under such circumstances.
In the future, Peralta and her team say an investigation into aborted fetuses should be undertaken. Right now, the research was limited to a small sample size that did not factor in a number of elements. Still, the team concludes, "the research presented here is pioneering to the extent that it links prenatal stress to the sex of newborns."
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Stay in touch with Derek on Twitter and Facebook. His most recent book is "Hero's Dose: The Case For Psychedelics in Ritual and Therapy."
The cost of world peace? It's much less than the price of war
The world's 10 most affected countries are spending up to 59% of their GDP on the effects of violence.
- Conflict and violence cost the world more than $14 trillion a year.
- That's the equivalent of $5 a day for every person on the planet.
- Research shows that peace brings prosperity, lower inflation and more jobs.
- Just a 2% reduction in conflict would free up as much money as the global aid budget.
- Report urges governments to improve peacefulness, especially amid COVID-19.
What is the price of peace?
Or put another way, how much better off would we all be in a world where armed conflict was avoided?
Around $14.4 trillion in 2019, according to the Institute for Economics and Peace (IEP) which crunched the numbers. That's about $5 a day for every person on the planet.
To give some context, 689 million people - more than 9% of the world's population - live on less than $1.90 a day, according to World Bank figures, underscoring the potential impact peace-building activities could have.
Just over 10% of global GDP is being spent on containing, preventing and dealing with the consequences of violence. As well as the 1.4 million violent deaths each year, conflict holds back economic development, causes instability, widens inequality and erodes human capital.
Putting a price tag on peace and violence helps us see the disproportionately high amounts spent on creating and containing violent acts compared to what is spent on building resilient, productive, and peaceful societies.
—Steve Killelea, founder and executive chairman, Institute for Economics & Peace (IEP)
The cost of violence
In a report titled "The Economic Value of Peace 2021", the IEP says that for every death from violent conflict, 40 times as many people are injured. The world's 10 most affected countries are spending up to 59% of their GDP on the effects of violence.
Grounds for hope
But the picture is not all bleak. The economic impact of violence fell for the second year in a row in 2019, as parts of the world became more peaceful.
The global cost dropped by $64 billion between 2018 and 2019, even though it was still $1.2 trillion higher than in 2012.
In five regions of the world the costs increased in 2019. The biggest jump was in Central America and the Caribbean, where a rising homicide rate pushed the cost up 8.3%.
Syria, with its ongoing civil war, suffered the greatest economic impact with almost 60% of its GDP lost to conflict in 2019. That was followed by Afghanistan (50%) and South Sudan (46%).
The report makes a direct link between peace and prosperity. It says that, since 2000, countries that have become more peaceful have averaged higher GDP growth than those which have become more violent.
"This differential is significant and represents a GDP per capita that is 30% larger when compounded over a 20-year period," the report says adding that peaceful countries also have substantially lower inflation and unemployment.
"Small improvements in peace can have substantial economic benefits," it adds. "For example, a 2% reduction in the global impact of violence is roughly equivalent to all overseas development aid in 2019."
Equally, the total value of foreign direct investment globally only offsets 10% of the economic impact of violence. Authoritarian regimes lost on average 11% of GDP to the costs of violence while in democracies the cost was just 4% of GDP.
And the gap has widened over time, with democracies reducing the cost of violence by almost 16% since 2007 while in authoritarian countries it has risen by 27% over the same period.
The report uses 18 economic indicators to evaluate the cost of violence. The top three are military spending (which was $5.9 trillion globally in 2019), the cost of internal security which makes up over a third of the total at $4.9 trillion and homicide.
Peace brings prosperity
The formula also contains a multiplier effect because as peace increases, money spent containing violence can instead be used on more productive activities which drive growth and generate higher monetary and social returns.
"Substantial economic improvements are linked to improvements in peace," says the report. "Therefore, government policies should be directed to improving peacefulness, especially in a COVID-19 environment where economic activity has been subdued."
The IEP says what it terms "positive peace" is even more beneficial than "negative peace" which is simply the absence of violence or the fear of violence. Positive peace involves fostering the attitudes, institutions & structures that create and sustain peaceful societies.
The foundations of a positively peaceful society, it says, are: a well functioning government, sound business environment, acceptance of the rights of others, good relations with neighbours, free flow of information, high levels of human capital, low levels of corruption and equitable distribution of resources.
The World Economic Forum's report Mobilizing the Private Sector in Peace and Reconciliation urged companies large and small to recognise their potential to work for peace quoting the former Goldman Sachs chair, the late Peter Sutherland, who said: "Business thrives where society thrives."
Reprinted with permission of the World Economic Forum. Read the original article.
The evolution of modern rainforests began with the dinosaur-killing asteroid
The lush biodiversity of South America's rainforests is rooted in one of the most cataclysmic events that ever struck Earth.
