"Compassion is a most important part of life," said the Dalai Lama, a spry 76-year-old named Tenzin Gyatso.He is the spiritual head of Tibetan Buddhism as well as a political leader, traveling the world advocating autonomy for his country, which is controlled by China. He lives in exile in India.The 1989 Nobel Peace Prize winner told a hushed audience at Viejas Arena that a sense of belonging and community brings with it a need for responsibility and concern for others."Now seven billion human beings -- actually human brothers, sisters -- mentally, emotionally, physically," he said. "We are same."He said everyone has the same capacity for good and destruction.Noting that he was speaking to a relatively young audience, he said, "You have opportunity to make happy world.""Pain and pleasure, satisfaction, joyfulness, mental level -- all those joyfulness satisfaction through sensory sort of experiences, is very temporary, very limited," the Dalai Lama told the crowd. When he came onto the stage, he was given a key to the city by Mayor Jerry Sanders."It's my honor to present his holiness with the key to our city on behalf of the citizens of San Diego," said Sanders. "Throughout his teachings, his holiness encourages all of us to strive for a better future, through peace and compassion for others. With this key, we offer his holiness a promise to keep working for a brighter tomorrow."As one of the city's highest honors was delivered by Sanders, in return, Sanders was honored with a blessed Tibetan scarf from the Dalai Lama. The Dalai Lama also spoke about what's important at the end of one's life as well. "At the beginning of our life, affection is so important role; at the time of dying, or illness, affection, very important role," he added. He also warned about placing too much importance on material goods. "Material development alone will not bring genuine inner peace." Like he did in talks on Wednesday at UC San Diego and the University of San Diego, he donned a visor sporting the name of the host school. He discussed climate change at UCSD and later was awarded the USD Medal of Peace.The crowd at the SDSU event was well over twice the size of Wednesday's events, however, and before the speech, long lines wound outside the arena of attendees waiting to go through security checkpoints. Those who got in early watched a Native American dance performance and other entertainment.For some, it took few words to describe the impression he left on the crowd as they started to file out of the auditorium. "Wow," said Dalai Lama supporter Morton Levy. "Very, very exciting and impressive; amazing." Others told 10News it was a life-changing experience. "I just about cried," said San Diegan Crystal Gilbert. "I have wanted for years to see the Dalai Lama talk and today was a once in a lifetime chance." The Dalai Lama gave an interview of around 20 minutes at KPBS Radio, and was set to travel to Long Beach for his next appearance on Saturday.