“You could bring him a problem at any level of psychology, and he could help you think it through,” Gilbert said.

Hackman, who came to Harvard in 1986 after 20 years at Yale, conducted research on team dynamics that had substantial real-world implications, including new research methodology within the intelligence community for studying teams and an alternative method for training cockpit crews.

Hackman received numerous awards for his work, among them the Distinguished Scientific Contribution Award within the American Psychological Association’s division on industrial and organizational psychology.

But despite the accolades, Hackman maintained a steadfast humility that translated into a distaste for boasting throughout his years of teaching.

“He looked askance at people who spent a lot of time tooting their own horn,” Gilbert said. “Richard had a silencer on his horn, so even when he did remarkable things, he would work to make sure nobody found out about them.”

Even after they had been friends for nearly 20 years, Gilbert said, he only learned about Hackman’s work for the women’s basketball team after he spotted Hackman at one of the games.

But coupled with this humility was what Hackman’s wife Judith D. Hackman described as her husband’s distinctly “contrarian” streak.

“He was often the one who voted no, and everybody else voted yes,” she said. “His 'no' was probably the right thing to say.”

Gilbert agreed, calling his friend “a moral beacon” who was “unendingly concerned with what was right and what was wrong.”

Yet those who were close to Hackman said it is the little things that are most irreplaceable about him.

For Judith Hackman, it will be her husband’s daily phone calls; for Gilbert, it will be Hackman’s penchant for barbecue.

“In the last two decades he and I probably hit every good barbecue stand within a 50-mile radius of Boston,” Gilbert said. “I will forever more be eating brisket and ribs by myself.”

Aside from his wife Judith, Hackman is survived by two daughters, Julia B. Proffitt and Laura D. Codeanne; two sons-in-law, W. Trexler Proffitt and Matthew J. Codeanne; and four grandchildren, George R., Lauren E., and Edward M. Proffitt, and Mattox J. Codeanne.

—Staff writer John P. Finnegan can be reached at johnfinnegan@college.harvard.edu.