A hodgepodge of students, Muslim admirers, critics and classic rock fans packed Science Center C yesterday to hear Yusuf Islam, formerly Cat Stevens, speak about his ongoing spiritual journey.

The speech, titled "In Search of the Center of the Universe," is part of the singer's tour of New York and Boston, which included a stop at Columbia University. The event was sponsored by the Harvard Islamic Society, the Islamic Society of Boston and the Harvard Foundation for Intercultural and Race Relations.

Frequently referencing both his own songs and the Koran, Islam described his youth as a rock star, his discovery of Islam, and how conversion has changed his life.

"You may be wondering why a rock star who had everything decided to come down from the stars, put his head on the ground, hang up his guitar and say goodbye to that kind of world," Islam said at the beginning of his speech.

Islam discussed his path from childhood in London to becoming a rock star during a time when British rock was at its height.

Born in London in 1948 with the name Stephen D. Georgiou, Islam changed his name to Cat Stevens before he released Mathew & Son in 1966, the first of several popular albums. He is best known for his 1970 album, Tea for the Tillerman, which included the hits "Wild World" and "Father and Son."

But Islam said he was unsatisfied with the fast-paced lifestyle of a rock star. After a bout with tuberculosis at age 19, he began what he described as a "spiritual quest" that culminated in his conversion to the Muslim faith in 1977. At that point, he also changed his name.

Islam said the public has never understood his conversion and has continued to have many misconceptions about his life.