In other words, knowledge of historical events and precedents in the field of education allows teachers to consider a broader array of conditions and means in the search for solutions to educational problems than would be possible if their training consisted solely of observation and practice in actual classrooms. This knowledge base contains the past influences and current options available in education as a field from which a teacher can draw in making decisions about the best course to follow in the classroom. Classrooms are complex and dynamic places. Any classroom changes from minute to minute. The situations you encounter in any human environment are too numerous, complex and dynamic ever to be mastered.
Human behavior is complex.
Every human response is influenced by too numerous of variables to memorize every exact way they affect one another. They change the teaching environment and situation constantly. It is therefore impossible for teachers to learn through practice or observation a response for every situation that will occur in their classroom. Consider Medicine, another professional field involving human behavior. A doctor makes a diagnosis about a patient after careful observation of that patient.