Harry L. Rosenzweig, an influential mathematics professor who had been chairman of the math department at McDaniel College, died Friday of pancreatic cancer at his Westminster home.
He was 72.
"Harry was very popular with math majors and, in general, anyone who took a course with him and was willing to work hard had a very positive experience," said Robert P. Boner, a colleague who taught math at what is now McDaniel College for 37 years before retiring in 2007.
"He was a demanding teacher but was also was very helpful outside of the classroom with both help and advice," said Dr. Boner.
The son of accountants, Dr. Rosenzweig was born and raised in New Haven, Conn., where he graduated in 1957 from James Hillhouse High School.
He earned a bachelor's degree in math in 1961 from the Massachusetts Institute of Technology and his master's in 1963 from the University of Arizona.
He had been an instructor at the University of Arizona and the University of Virginia, from which he earned his doctorate in 1967.
He was an assistant professor of math at Haverford College from 1967 until 1971, when he joined the faculty of what was then Western Maryland College.
Dr. Rosenzweig was chairman of the college's math and computer science department from 1984 to 1995. He had also been a member of the department's problem-solving g roup.
Daniel A. Williams, who taught languages at McDaniel for 31 years until retiring in 2004, was Dr. Rosenzweig's tennis partner.
"Harry believed in excellence and being the best you could be," said Dr. Williams.
Dr. Rosenzweig's classes were known for their challenging homework and examinations. Students who thought they could coast their way through soon found otherwise.
Dr. Rosenzweig's academic area of expertise included topology, which is a way of studying and describing different kinds of spaces, set theory and logic, which prepared some of his math majors for careers with the federal government in cryptology.
For many years, he coordinated the testing of the department's majors in the William Lowell Putnam Mathematical Competition; under his tutelage, Western Maryland College students scored high marks on the six-hour test and ranked either 10th or 11th among small colleges in the nation.
He wrote numerous papers that were published in American Mathematics Monthly, The Mathematics Magazine and the College Mathematics Journal.
Dr. Rosenzweig had not retired at his death, and continued working until two months before the start of the 2011-2012 academic year, when he was diagnosed with the cancer that claimed his life.
In the days since Dr. Rosenzweig's death, Dr. Boner, who will be the eulogist at his funeral service, has been collecting email tributes and letters from former students, many of whom have gone on to careers in academia because of him.
"During many conversations in the math department lounge, Harry promoted the ideal of the liberal arts: that the study of philosophy, literature and mathematics leads to a fuller, a more satisfying life," wrote one former student.
"He encouraged me and others to study mathematics not with the goal of becoming mathematicians, but in the belief that this abstract study was the optimal way for us to develop our minds," wrote the student. "I am now a professor of mathematics at Bridgewater College. I try to model my teaching very much on the teaching style of Dr. Rosenzweig who had such a large impact upon my education."
Other former students wrote that he linked the study of math with "literature, music, politics and Americana" and showed "how solutions to [math problems] were often found in disparate corners of the globe," observed another.
Another student recalled the major lesson that Dr. Rosenzweig impressed upon them, especially those who planned careers in education: "Be over-prepared, care about your students, care about your subject matter, and care about how your students learn the subject matter."
From 1977 to 1978, Dr. Rosenzweig was a visiting scholar at the University of California at Berkeley, and beginning in the 1990s taught summers at Cornell University in Ithaca, N.Y. He also had been the recipient of several National Science Foundation Fellowships through the years.
He was an avid tennis player.
"Harry was a good, competitive tennis player," said Dr. Williams. "He had won several Carroll County Tennis Association tournaments in the 35-and-over group."
He also enjoyed hiking, said his wife, the former Frances Richards, whom he married this year.
He was an aficionado of the Victorian period and collected R.S. Prussia porcelain, which was produced by Reinhold Schlegelmilch from the late 1800s to World War I in Suhl, Germany. Other collecting interests included elegant Victorian hatpins.
Services will be held at noon Wednesday at Sol Levinson & Bros., 8900 Reisterstown Road, Pikesville.
In addition to his wife, Dr. Rosenzweig is survived by a son, Scott Rosenzweig of Bozeman, Mont.; two daughters, Janis Davisson of Crofton and Laura Reames of Towson; a sister, Helen Santis of Concord, Mass.; and six grandchildren. An earlier marriage to the former Susan Shanken ended in divorce.
An earlier version of this obituary misstated the years that Mr. Rosenzweig was chairman of the McDaniel College math and computer science department. The Baltimore Sun regrets the error.