Interim Dean of the Faculty Jeremy R. Knowles’ plan for Faculty growth, which prioritizes hiring in the sciences and engineering, has been met with enthusiasm among scientists but with mixed support from professors in the humanities and social sciences.

Knowles, who has championed the sciences during his return to University Hall this academic year, released a letter earlier this month outlining a plan for faculty growth and renewal, calling for most of the net growth over the next three years to take place in sciences and engineering.

“The direction is surely wise and appropriate,” said Edward L. Glaeser, the Glimp professor of economics. “Amazing things have been happening in the sciences in the last 15 years and it is absolutely critical that Harvard be in the forefront of scientific learning.”

The chair of organismic and evolutionary biology, Andrew A. Biewener, echoed Knowles’ sentiments and reiterated his call for growth in the sciences.

In terms of investing in the sciences, “compared to peer institutions, Harvard lags,” said Biewener, who is the Lyman professor of biology.

In his letter, Knowles—a chemist—wrote that many people, including the University’s top governing bodies, have concluded that “FAS has systematically underinvested in science.”

But one humanity professor said that there is concern that the science growth will come at the cost of the vitality of the humanities and social sciences.

“Obviously not everybody’s happy about it,” said Jay M. Harris, the Wolfson professor of Jewish studies and chair of the Near Eastern languages and civilizations Department.

“In an ideal world, we wouldn’t deal in zero sums,” Harris said, “In an ideal world, there would be a nice campaign and the humanities and social sciences would be taken care of also. We need to grow too.”

FAS currently faces a budget shortfall, in part a result of a hiring surge that has significantly boosted its size.

The Faculty began expanding in 1999, and since then has grown from 615 to 723—the largest surge in FAS appointments since the 1960s. The majority of those appointments took place within the humanities and the social sciences.

Knowles said he now wants to focus the second round of hiring in the sciences.

Knowles said he now wants to focus the second round of hiring in the sciences.

Over the next three years, the net size of the Faculty is expected to increase by 18.

But the expected retirement of 120 professors—39 in the humanities, 43 in the social sciences, 14 in the life sciences, 15 in the physical sciences, and 9 in the School of Engineering and Applied Sciences—will allow the FAS dean to further shape the distribution of the Faculty across the disciplines.

But with Knowles scheduled to step down as interim dean in late June—and with President-elect Drew G. Faust yet to name Knowles’ successor—some professors have questioned whether the dean’s plan will proceed even after his tenure ends.

“It will most certainly be high on the agenda for the next dean,” said Everett I. Mendelsohn, a history of science professor and member of the Faculty Council, the governing body of the FAS.

“Dean Knowles laid out the issues as he sees them. It’s a highly laudable step, but the real discussion is just beginning. Next year we will see some intense discussion.”

—Staff writer Carolyn F. Gaebler can be reached at cgaebler@fas.harvard.edu.