Confirmation bias

Seeking and weighting evidence that supports what you already believe, and discounting what does not.

It's the most damaging bias in research work because it operates invisibly and feels like diligence. Once you've written a positive thesis, you read the next disclosure looking for confirmation, and you find it, because most disclosures contain something for everyone.

Structural defences are the ones that work. Write the bear case before the bull case. Seek out the best argument against the position, and ignore the weakest. Record in advance what evidence would falsify the thesis.

Find the person who disagrees and understand why.