In the a recent episode of EconTalk, where Russ Roberts interviews the great Bill James, the father of sabermetrics, they discuss the distinction between science and expertise as James delineates it in a great essay called “The Note”. It begins:
Handwriting expertise, more clearly than any other field that I know of, illustrates the difference between science and expertise. Science uses general rules and principles, understood by millions of people, to work toward increasing our shared understanding of the world in which we live, a key word being “shared”. What is learned by the scientist is in no sense the property of the scientist, if it is truly science and not commerce. If in our field we were to discover, for example, that tall hitters do best against tall pitchers and short hitters do best against short pitchers, the value in this would not be to me, but to a baseball team by way of its manager. The manager would be as much the owner of this knowledge as the analyst who discovered it. Crucial to that fact—to the shared nature of its ownership—is how it is known. If I were to say that I know that tall hitters hit best against tall pitchers and you should believe me because I am an expert in this field, no one would believe me and no one should believe me. Others would believe me only if (1) I were to present evidence demonstrating that it is true, and then only if (2) others were able to study the same subject and reach the same conclusion. Studying the same subject and reaching the same conclusion or a different conclusion does not require expertise limited to a small cadre of persons; it merely requires that we apply the rules of scientific enquiry which are universally owned and widely understood. Shared principles yield shared knowledge.
Expertise, on the other hand, is the property of the expert. The only way that WE know that Document 1 and Document 2 were or were not written by the same person is that an expert says so. The only way to get a second opinion is to ask another expert. If the other expert cannot get access to the documents, you can’t get another opinion.
James is not the first to identify this division, but he puts it very well.