To show a study is to let people trace a scientist's past

The most important thesis of the task of scientists is to let non-expert people know the specialty. In case of a preparation for a scientific presentation, scientists should imagine the day when they were not experts. The good scientist knows what people don't know because he is well imaginative. He is good at to remember the past himself. The good presentation is to show the way how he became to know his specialty: how he knew the technical term and how he knew the technical methods. If he can successfully achieve letting the audience trace his way, they will understand the excellence of his study finally.