My freshman American literature course presented me with many revelations, but one of the most indelible happened not inside the auditorium classroom where, twice a week, our professor stood onstage in front of more than a hundred 18-year-olds. Instead, it came as I stepped into the women’s restroom afterward, just in time to overhear two of my fellow classmates rhapsodizing over how cute the professor was, with particular attention lavished on his long, slightly bowed, denim-clad legs. I was naïve enough to be a bit shocked that girls my age would talk that way about such an exalted figure. And I felt a little sheepish, too, since I’d secretly been thinking the same thing myself.

Perhaps it’s possible to separate the thrill of encountering a fascinating mind from the fizz of libido, but I can’t imagine why anyone would want to.

Students sometimes nurse crushes on their teachers, and teachers sometimes lust after their pupils; these are facts of life so commonplace as to have become the ultimate cliché: a porn motif. Like many vaguely parental relationships, the pedagogic one can have a strong and unsettling erotic undertow. My fellow students and I probably wouldn’t have looked twice at our prof if we’d met him at the bus stop or waiting in line at the campus café; he was at least 35—maybe even 40! Like many young women, however, we were far from immune to the mystique of a man who can command the admiring attention of a crowd, and if he was like most men, he was sensible to the flattery of all those rapt faces. Yet at the root of this queasy dynamic was genuine intellectual excitement. His class set off a series of firecrackers in my understanding of books, ideas whose impact I can still recollect vividly. Perhaps it’s possible to separate the thrill of encountering a fascinating mind from the fizz of libido, but I can’t imagine why anyone would want to. That species of desire makes ideas feel more vitally connected to our bodily lives and tells us that passions can be spurred by qualities deeper than six-pack abs.

Whether students or their teachers should ever act on such desires, however, has never been an untroubled question. To do so raises the possibility of both favoritism and exploitation. If we think of the university as a purely professional realm, where services are exchanged for a fee among rational economic actors, then sexual relationships seem clearly out of bounds, as they are in most workplaces, especially between supervisors and subordinates. But if the academy is something more than that, if, as many of its members hope, it’s a place where deep and lasting collegial bonds are formed, where mentors and protégés can become close friends and where young lives are transformed by a galvanic encounter with knowledge and their own latent capabilities, how can we possibly stamp out the potential for desire to arise? Perhaps what makes pedagogy so potent also makes it inherently erotic.

Lines in the debate have been drawn more clearly in recent years. In February, for example, Harvard announced that it was banning all consensual “romantic or sexual” relationships between faculty members and undergraduates, regardless of whether the student is enrolled in any of the professor’s classes or is even in the same department (although faculty can still date graduate students if they don’t supervise their work). These and other revisions of university codes followed the announcement last year that the Department of Education would be investigating 55 colleges and universities for “possible violations of federal law over the handling of sexual violence and harassment complaints” under Title IX of the Education Amendments of 1972. (Harvard was found to have failed to comply with Title IX in responding to such accusations.)