Wei, who was released from prison for what Chinese officials say were medical reasons, suffered an angina attack on Tuesday and was hospitalized in Canada for heart tests before making his one-and-a-half hour public appearance at Harvard.

Standing under the bright lights of the Forum, Wei grew visibly tired after 45 minutes of open questions. As the capacity crowd of 800 stood in ovation, he asked forgiveness for not having the strength to answer any more.

Wei is part of the first generation ofdemocracy activists which came into prominence in1978. The 1989 Tiananmen Square protests, whichWang helped lead as a Beijing University student,are widely considered to have been the secondwave.

In 1978, during the post-Mao democraticmovement, posters demanding political reform werehung on a wall in Tiananmen Square.

The "Democracy Wall," erected shortly afterDeng Xiaopeng came into power, quickly gainedinternational attention and Wei's poster "TheFifth Modernization: Democracy" led the charge.

The Beijing Zoo electrician went from obscuregovernment worker to heralded and jailed activistin less than a year. Wei was sentenced to 15 yearsin prison in 1979.

After his release in 1993--mere days before acommittee was to decide on Beijing's bid to hostthe 2000 Olympics--Wei again ran into trouble,this time for speaking with the U.S. AssistantSecretary of State for Human Rights. He wassentenced to another 14 years of prison in 1995