The last thing anyone wants is for their surgeon to make a mistake. Similarly, no one wishes to cross a bridge that was constructed with an engineering design flaw. Mistakes are costly to society and can have tragic consequences.
So it is important that we train scientists and engineers to anticipate the very mistakes they might be inclined to make. For it is one skill to know how to do something right; but it is equally important to know how not to do something wrong. For bad decisions sometimes happen under the heat of pressure.
As the economy continues its contraction and universities consider replacing tenure track faculty with less costly lecturers, I am compelled to wonder what professors bring to the table. Why should we entrust our children's education to tenured faculty as opposed to lecturers?
By virtue of the arduous tenure review process, tenured professors have stretched their understanding of their discipline. They have applied it toward their research after graduate school and thus are more thoroughly apt to evince a contextual awareness of their field.
In my own research, for example, I have taken many dead ends; I have made mistakes and learned from them. This has enabled me to understand not only how to solve engineering problems correctly, but also how not to solve problems incorrectly. The research process, demanded by the tenure system, has taught me this; and I convey this understanding to students.
While students sometimes ask me how to solve a problem, they will more often demand to know where they went wrong in their own approach — be it on a problem or in the lab. It takes a greater master to advise a student how not to solve a problem incorrectly that it does to show them how to do it right. And when students benefit, so does society in the long run.
So before universities rush to replace faculty with less expensive lecturers in a classroom, we need to ask: do we wish only to teach students how to address problems correctly? If so, after we replace professors with lecturers, we might as well replace lecturers with interactive books. But if we wish to instill in students the ability to see the context of their disciplines, how to make choices, and how not to waste time or solve problems incorrectly, then they need the guidance of professors who have learned how not to make mistakes.