Did he? If someone approached this problem with a blank slated, looked at the evidence, formed an opinion, then wrote something to back their opinion, how coul

Did he? If someone approached this problem with a blank slated, looked at the evidence, formed an opinion, then wrote something to back their opinion, how could you tell them apart from someone who had an opinion and applied science to just advance their opinion? Assume both are average, and thus imperfect, writers.