Tenure - the lofty institution that guarantees lifetime job security at the University - does not come easily at Princeton.
And those who earn it find that the intensity of academic life at Princeton does not diminish at all after they receive their promotion.
Tenured astrophysics professor Edwin Turner said he believes professors' desire to continue their studies prevents much "dead wood" from collecting in the Princeton faculty.
History professor Laura Engelstein, who is also tenured, agreed. "In our department, people write books because they love to," she said. "They don't seem to suffer from 'Now what?' or 'Now I don't have to try so hard.' "
"Some people argue that tenure makes professors complacent and that having insecure jobs would keep them on their toes," Engelstein said. "In my observation, getting tenure frees people to participate more wholeheartedly in department life and to take intellectual risks. In short, I'm for it."
For Turner, tenure allowed him to conduct research on gravitational lenses and dark matter during a time when those topics were not receiving a great deal of attention from other scientists. Today, Turner is known for this work.
While the promotion gave him more freedom in his research, Turner said his desire to succeed was not affected. "It was kind of like finding out you are not going to get shot next week," he said. "It removes pressure, but not much changes."
Tenure also gives professors an incentive to stay at the University when they might be earning more money in the private sector, Turner noted.
Michael Hecht, a chemistry professor who received tenure in 1996, also said the promotion allows a professor to pursue an unconventional study without worrying about his or her employment. With tenure, faculty are "more functional, more competent and more efficient without that fear," he said.
Faculty members undergo a rigorous evaluation process and are considered for the promotion based on their accomplishments, both in research and teaching, according to chemistry professor Maitland Jones. Jones has served on the committee that oversees the final steps in the process to determine who receives tenure.
Nevertheless, no strict guidelines exist for the number of years a professor must be at the University to be considered for tenure, said associate dean of the faculty Katherine Rohrer. Of the assistant professors who are reviewed in a given year, roughly half of them receive the promotion.
Hecht said professors enter into a university's faculty hoping to gain more extensive knowledge of their academic discipline. He noted that tenure must be a key part of that goal because it assures a faculty member continued employment.
Tenured history professor Daniel Rodgers explained that tenure was adopted by American universities after World War I to protect a professor's freedom to express ideas - even controversial ideas - at an institution of higher learning. Tenure guarantees a professor can not be fired because of the ideas he or she teaches.
Rodgers added that he believes bioethicist Peter Singer's recent appointment at the University reminded many of the reasons for tenure.