Into his early 90s, Jack Cogan was still going for runs along the Charles River, striding toward a future that kept offering the possibility of contributing more.
“Each new decade for me has been full of interest, challenge, and excitement,” he had written years earlier, at 83. “I am blessed beyond measure with good health, energy, and happiness,” he wrote, adding that “I know this is a temporary gift for which I give prayerful thanks each day.”
Mr. Cogan, who was 93 and lived in Cambridge when he died Friday, made ample use of those decades.
A former chairman and managing partner of the prominent law firm Hale and Dorr, he had essentially a second, parallel career as a top official in many capacities at what was then a mutual funds firm called the Pioneer Fund and is now Amundi Pioneer Asset Management.
And as if that didn’t fill each day, his many civic roles included formerly chairing the Board of Trustees at the Museum of Fine Arts in Boston and serving in board leadership positions for other institutions, such as the Boston Symphony Orchestra.
Mr. Cogan was so involved with Boston’s arts world that in 2005 he was elected a fellow of the American Academy of Arts and Sciences. He also served on numerous other boards, including formerly chairing the trustees of what is now Boston Medical Center.
Offering advice to aspiring lawyers in 2010, the year he turned 84, Mr. Cogan was both cautioning and encouraging.
“If you’re a natural workaholic — which unfortunately I am, genetically, I guess — you must be careful not to be so drawn into your professional life that there is time for little else,” he said in an interview with Harvard Law Today.
“It’s as if you were in a giant centrifuge,” added Mr. Cogan, a graduate of Harvard College and Harvard Law School, and a 2009 Harvard Medal recipient. “You have to constantly try to avoid being drawn into the center and rather swim to the edge to reach other activities that enrich your life.”
At his law firm, which is now WilmerHale, co-managing partner Susan Murley recalled Mr. Cogan as “a leader in the Boston business community and an ardent philanthropist.”
Mr. Cogan, who joined Hale and Dorr in 1952, “left a meaningful mark on our culture and our standards,” Murley said in a statement. “Since he retired from the firm in 1999, he was a regular visitor to our Boston office offering many thoughtful suggestions on various aspects of the firm and firm life.”
He was, she added, “a brilliant counselor and a staunch colleague.”
Mr. Cogan brought his wider life perspective to all endeavors, including Amundi Pioneer, where he began working more than 60 years ago.
Lisa Jones, the firm’s CEO, met with him once or twice a month for the past five years “to talk about the industry, to get his perspective on certain challenges of running the business.”
Always sporting a bowtie, Mr. Cogan “was the ultimate gentleman,” she said. He arrived prepared for every meeting, including one earlier this month, and brought along materials to share.
“He wasn’t shy about disagreeing with perspectives and asking tough questions,” Jones said, “but he did it in a manner that was elegant, professional, and caring.”
Matthew Teitelbaum, the director of the Museum of Fine Arts, said in a statement that Mr. Cogan “was an inspiring leader and a true believer in the power of the creative spirit. He was generous, thoughtful, and optimistic, believing that by working together we could create a better world. He made so many of us better because he asked the questions that made us really think. He was a hero to many.”
Mr. Cogan, a former vice chairman of the Boston Symphony’s Board of Trustees and of its Board of Overseers, “was a true giant in the BSO’s history, as a man who not only witnessed so much of it, but also shaped it for decades,” BSO chief executive Mark Volpe said in a statement.
“A soft-spoken man who conveyed incredible gravitas, John led by example, and when he talked, everyone listened,” Volpe added. “He often encouraged the BSO’s trustees to ‘look in the mirror’ when making decisions about the BSO’s future to ensure that they each understood their own responsibilities to the organization.”
Mr. Cogan also formerly chaired the Investment Company Institute, an association based in Washington, D.C.
“Jack Cogan was a powerful voice for effective regulation and strong service to the 100 million Americans who invest in regulated funds,” Paul Schott Stevens, chief executive of the institute, said in a statement. “His wisdom, long experience, and breadth of knowledge carried enormous weight with his peers, and on many occasions a few words from Jack could clarify the thorniest of issues and show the way forward.”
While at Harvard Law, Mr. Cogan took courses at Harvard Business School, a helpful preparation for his roles as a lawyer and president of a mutual funds firm. In the mid-1970s, he estimated that between the two jobs, he often traveled 100,000 to 150,000 miles a year.
He also was a Democratic Party activist locally and statewide.
“I am forever amazed at how exciting each decade continues to be,” he wrote for the 50th anniversary report of his Harvard class.
Born in 1926, John Francis Cogan Jr. was the oldest of three children whose parents were John Cogan Sr. and Mary Galligan.
After graduating from Melrose High School, Mr. Cogan enlisted in the Navy during World War II and served during the invasion of Okinawa.
Returning home, he was allowed to choose which Harvard College class to enter. He picked 1949 so he and his brother, Charles, could graduate together.
In 1951, Mr. Cogan married Mary Hart. They had four children and their marriage ended in divorce.
He married Mary Cornille in 1989. They traveled frequently, often visiting museums and occasionally collecting artworks.
“Music and art were two things we really shared a passion for,” she said, adding that her husband “always had a twinkle in his eye. He had a wicked sense of humor and loved to laugh.”
In 1952, Mr. Cogan graduated from Harvard Law, to which he donated $6 million in 2009 to establish the Cogan Fund for International Legal Studies.
“In my years as dean, I have benefited from his counsel and wisdom in countless ways,” Elena Kagan, who was then Harvard Law’s dean and is now a US Supreme Court justice, said then in announcing his gift.
In addition to his wife, Mary, Mr. Cogan leaves three sons, Peter of Seattle, Jonathan of Arlington, Va., and Gregory of Norwell; a daughter, Pamela Cogan Riddle of Atherton, Calif.; and nine grandchildren.
The family is planning a private funeral. A public memorial gathering will be announced.
With so many work and community commitments, “life is a balancing act,” Mr. Cogan told Harvard Law Today.
Remaining involved with a multitude of organizations “narrows the amount of free time that one would otherwise have and often makes for long days,” he added, “but the rewards in terms of enrichment and the expansion of my knowledge and interests have been great and personally satisfying.”
Bryan Marquard can be reached at email@example.com.