BENNO SCHMIDT: Mitch Daniels’s Gift to Academic Freedom: His skepticism about the merits of a sacrosanct liberal history textbook has sparked an overdue debate.

Politicians can’t dictate course syllabi or reading lists in higher education. But nor should faculty be allowed to engage in indoctrination and professional irresponsibility without being held to account. And yet, over the past 50 years, that is essentially what has happened. The greatest threat to academic freedom today is not from outside the academy, but from within. Political correctness and “speech codes” that stifle debate are common on America’s campuses. The assumption seems to be that the purpose of education is to induce correct opinion rather than to search for wisdom and to liberate the mind.

If academics want to continue to enjoy the great privilege of academic freedom, they cannot forget the obligations that underline the grant of that privilege. The American Association of University Professors itself recognized those obligations in its seminal statement, the 1915 Declaration of Principles on Academic Freedom, which is today nearly forgotten: “If this profession should prove itself unwilling to purge its ranks of the incompetent and unworthy, or to prevent the freedom which it claims . . . from being used as a shelter for inefficiency, for superficiality, or for uncritical and intemperate partisanship, it is certain that the task will be performed by others.”

It’s time that college and university trustees, presidents and faculty made a concerted effort to ensure and engender a culture of academic freedom—and responsibility. If integrity is not maintained from within, the public will attempt to impose it from without. Mr. Daniels’s emails have sparked a needed debate on this defining value.

You can’t criticize ideas here, gentlemen. This is a university!