Daniel W. Dietrich II, 73, a self-effacing philanthropist who valued quiet exploration as much as artistic adventure, died Tuesday, Sept. 1, at Paoli Hospital.

Mr. Dietrich, who lived in Chester County, was heir to a family conglomerate that once counted Luden's cough drops among its assets. He was vice president of Luden's, based in Reading, for a time, but his tastes ultimately ran more toward cultural activities than business endeavors.

A longtime board member and supporter of the University of Pennsylvania's Institute of Contemporary Art, Mr. Dietrich made a bold statement about his interests this year when he gave $10 million to ICA to form an endowment that would enhance the scope and flexibility of the institution's curatorial efforts.

The gift led ICA director Amy Sadao to characterize Mr. Dietrich as "a courageous arts patron" willing to fund something with an unknown outcome.

"We wanted to get at the core of ICA and what it has been since its founding," Sadao said at the time of the gift. "That means . . . giving artists the opportunity to venture into new territory and even possibly to see work in a new light. That takes time."

Mr. Dietrich said that he saw his gift as providing time for curators and artists to "percolate ideas" and "approach artwork from the meditative side."

At the same time that Mr. Dietrich was finalizing this gift, he was arranging for the purchase of Roxy Paine's monumental public sculpture Symbiosis, a silvery, stainless, treelike form at the head of the Benjamin Franklin Parkway. He acquired the work for an undisclosed price, which allowed the Association of Public Art to retain the work for Philadelphia in place, near Mark di Suvero's red Iroquois, installed by the association in 2007.

"He was a very astute collector, and a passionate collector of - and advocate for - contemporary art," said Timothy Rub, director of the Philadelphia Museum of Art, where Mr. Dietrich was a member of the contemporary art committee, the Anne d'Harnoncourt Society, and the Campaign Cabinet.

Mr. Dietrich also endowed the museum's Theodor Siegl conservator of paintings chair, honoring the late conservator, who carried out the first major preservation work on Thomas Eakins' The Gross Clinic, now owned jointly by the museum and the Pennsylvania Academy of the Fine Arts.

Mr. Dietrich graduated from Hamilton College with a bachelor's degree in art history. He remained actively involved with Hamilton as an alumnus, and served on the architectural committee that designed the Wellin Museum, which includes a gallery named in his honor.

He also was an actor at the Theatre of the Living Arts in the early 1960s, when Andre Gregory made it a mecca for avant-garde performance. Mr. Dietrich took the stage with Morgan Freeman, Wallace Shawn, and many others.

He starred as Malatesta in the film Malatesta's Carnival of Blood in 1973, and later appeared in George Romero's Dawn of the Dead in 1978.

His foray into low-budget filmdom eventually took a backseat to his deeper cultural engagements. But acting and theater work seemed to ground his understanding of all the resources needed to bring an artist's vision to life.

"All involved work feverishly to create something ephemeral," he said. "The action happens behind the scenes, so when the curtain rises, we have the stillness."

Mr. Dietrich is survived by his partner of recent years, Deborah Ullman, and sons, William S. Hildreth, Daniel W. III, and Adam.

Information on services and the cause of death was unavailable.

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