I have not read the book the article references. However, in reference to what Mr. Hacker and Ms. Dreifus call the "immorality" of using adjunct professors, the article's author does not address the fact that there are potentially very good reasons why the use of adjuncts is increasing.
In engineering, for example, adjunct professors may come from industry and provide students with perspective and experience full-time professors may not provide.
Adjunct professors may choose to teach as adjuncts because they have a passion and a talent for teaching they want to pursue without the pressures of publication. Many full-time professors may readily admit that the pressures of producing academic work causes the quality of their teaching to decrease. Perhaps this is one reason Yale offers its professors time so that both the quality of teaching and research remains high.
Some departments opt to hire adjunct professors because its set of full-time professors does not have the expertise to offer a course in a particular area of the field. While this may seem more applicable to technical fields, any department that opts to do this can provide students with more diversity and variety in course offerings over an academic year and over a student's academic career.
In engineering, for example, adjunct professors may come from industry and provide students with perspective and experience full-time professors may not provide.
Adjunct professors may choose to teach as adjuncts because they have a passion and a talent for teaching they want to pursue without the pressures of publication. Many full-time professors may readily admit that the pressures of producing academic work causes the quality of their teaching to decrease. Perhaps this is one reason Yale offers its professors time so that both the quality of teaching and research remains high.
Some departments opt to hire adjunct professors because its set of full-time professors does not have the expertise to offer a course in a particular area of the field. While this may seem more applicable to technical fields, any department that opts to do this can provide students with more diversity and variety in course offerings over an academic year and over a student's academic career.