Researchers in science often begin studies with a belief in mind and discount findings that discount their belief.
Failure to replicate challenges studies.
“A report on the issue, published in Nature this May, found that about 90% of some 1,576 researchers surveyed now believe there is a reproducibility crisis in science.”
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The failures particularly in biology, psychology and medicine.
Psychology is not a science, any more than is politics. A degree in “political science” means a degree in the history of politics and studies in particular areas of politics. “How political systems work” is not a science.
Dollars measured in billions go to downright false ideas.