The history of science is also a history of people resisting new discoveries that conflict with conventional wisdom.

When Galileo promoted Copernicus’ theory that the Earth revolves around the sun – counter to church doctrine about the Earth being the center of the universe – he wound up condemned by the Roman Inquisition in 1633. Charles Darwin’s theory of evolution – that new species develop as a result of natural selection on inherited traits – ran into opposition because it contradicted long-held scientific, political and religious beliefs. Alfred Wegener’s 1912 proposal that Earth’s continents move relative to each other – the theory of continental drift – was rejected for decades, in part because scientists held fast to the traditional theories they’d spent careers developing.

These kinds of examples aren’t only historical, unfortunately. We’re used to hearing about how the general public can be dense about science. You might expect some portion of everyday folks to take their time coming around on truly groundbreaking ideas that run counter to what they’ve always thought.

But scientists, too, hold their own personal beliefs – by definition, based on old ways of thinking – that may be holding back the innovation that’s at the heart of science. And that’s a problem. It’s one thing for an average Joe to resist evolving scientific theories. It’s quite another if a scientist’s preconceived notions holds us back from discovering the new and unknown – whether that’s a cure for Zika or a cutting-edge technology to combat climate change.

Personal beliefs as publication roadblocks

Real scientific progress occurs when laboratory or field research is reported to the public. With luck, the finding is accepted and put into practice, cures are developed, social policies are instituted, educational practices are improved and so on.

This usually occurs though publication of the research in scientific journals. There’s an important step between the lab and publication that laypeople may not know about – the evaluation of the research by other scientists. These other scientists are peers of the researcher, typically working in a closely related area. This middle step is commonly referred to as peer review.

In a perfect world, peer review is supposed to determine if the study is solid, based on the quality of the research. It’s meant to be an unbiased evaluation of whether the findings should be reported via journal publication. This important step prevents sloppy research from reaching the public.

However, in the real world, scientists are human beings and are often biased. They let their own beliefs influence their peer reviews. For example, numerous reports indicate that scientists rate research more favorably if the findings agree with their prior beliefs. Worst of all, these prior beliefs often have nothing to do with science but are simply the scientists’ personal views.

‘But that’s counter to what I thought…’

How is this a problem for scientific innovation? Let’s look at how some personal beliefs could prevent innovative science from reaching the public.

“Minorities aren’t good at STEM.” The stereotype that “women are not good at math” is commonly held – and also happens to be incorrect. If a scientist holds this personal belief, then he is likely to judge any research done by women in STEM (Science, Technology, Engineering and Mathematics) more negatively – not because of its quality, but because of his own personal belief.

For instance, some studies have shown that female STEM applicants in academia are judged more harshly than their male counterparts. Because of this gender bias, it may take a female STEM researcher more time and effort before her work reaches the public.

Some racial minorities face similar kinds of bias. For example, one study found that black applicants are less likely to receive research funding from the U.S. National Institutes of Health than equivalently qualified whites. That’s a major roadblock to these researchers advancing their work.

“Comic books are low-brow entertainment for kids.” Here’s an example from my own area of expertise.

Comic book research is a relatively recent area of study. Perhaps because of this, innovative findings in psychology have been discovered by analyzing comic book images.

However, people often believe that comic books are just low-brow entertainment for kids. If a scientist holds this personal belief, then she’s likely to judge any psychology research using comic books more negatively. Because of this, scientists like me who focus on comic books may not be able to publish in the most popular psychology journals. As a result, fewer people will ever see this research.

“The traditional ways are the best ways.” A final example is a personal belief that directly counters scientific innovation. Often, scientists believe that traditional methods and techniques are better than any newly proposed approaches.

The history of psychology supplies one example. Behaviorism was psychology’s dominant school of thought for the first part of the 20th century, relying on observed behavior to provide insights. Its devotees rejected new techniques for studying psychology. During behaviorism’s reign, any talk of internal processes of the mind was considered taboo. One of the pioneers of the subsequent cognitive revolution, George A. Miller, said “using ‘cognitive’ was an act of defiance.” Luckily for us, he was defiant and published one of the most highly cited papers in psychology.

If a scientist believes the way we’ve always done things in the lab is best, then she’ll judge any research done using novel approaches more negatively. Because of this, highly innovative work is rarely published in the best scientific journals and is often recognized only after considerable delay.

How is this a problem for scientific progress?

Almost by definition, the most important and innovative scientific findings often go against people’s existing beliefs. If research that conforms to personal beliefs is favored, then any research that is based on new ideas runs the risk of being passed over. It takes a leap to imagine a round Earth when everyone’s always believed it to be flat.

When old ideas rule the day, scientific progress stalls. And as our world changes at an ever faster pace, we need innovative thinking to face the coming challenges.

How can scientists stop their personal beliefs from impeding scientific progress? Completely removing personal beliefs from these contexts is impossible. But we can work to change our beliefs so that, instead of hampering scientific progress, they encourage it. Many studies have outlined possible ways to modify beliefs. It’s up to scientists, and indeed society as well, to begin to examine their own beliefs and change them for the better.

After all, we don’t want to delay the next revolutionary idea in climate science, pioneering cure for cancer, or dazzling discovery in astronomy just because we can’t see past our original beliefs.