Wang Dan is a weary - and wary - man.
His voice is hoarse from giving talks and interviews in the run-up to the 25th anniversary of Tiananmen Incident. He offers his time generously but declines to elaborate on his mainland students who have taken his Chinese history course at the Taiwan university where he is now teaching.
What he stresses is that when they return to the mainland which he is barred from setting foot on, they take with them "greater passion and ideals in pushing for how China develops".
"Some students are still in contact," he said, in his first interview with the Singapore media. "But I can't say what they are doing now because of safety issues. I worry they can be in trouble due to their association with me."
The caution is understandable. This, after all, is the man who, as a 20-year-old Beijing University undergraduate armed only with conviction and a bullhorn - led fellow students in a massive seven-week protest movement in China's capital calling for political reforms. It later collapsed in bloodshed when the country's leaders ordered the students removed. Workers and other residents outside the square were gunned down.
His role earned Mr Wang the title of China's most wanted man, and two prison stints before he was shipped out to the United States in 1998. In 2009, after earning a PhD in history at Harvard, he left for Taiwan.
A quarter of a century after that fateful night in Beijing, Mr Wang, now 45, is clearly struggling with questions about what role and what relevance he can have in China's developments as an exile.
"Of course, there is this problem. The best is if I can go back to China, and play an active role there. But Beijing has blocked us from doing so. So all I can hope is for that day to come."
It seems an unlikely dream. Two years ago, Mr Wang and other Tiananmen dissidents submitted a petition asking to return. It was met with the same stony silence that greets calls for recognition of what happened on June 4.
For now, said Mr Wang, who is single, the role he has carved out for himself is that of a "public intellectual" who engages with his students - including the hundreds of young mainland Chinese who have taken his course at National Tsing Hua University. He is also active in commenting on cross-strait relations and has mentored young activists, including those who took part in the recent Sunflower movement.
"I think I am already doing the best I can given the circumstances, and I'm satisfied with what I have done so far."
Teaching his mainland students "the truth" about what happened in 1989 - as opposed to the official version that the Tiananmen students were launching a "counter-revolutionary rebellion" - is something Mr Wang holds very close to his heart.
"Our voices are not heard in mainland China and the people there don't know what really happened," he said.
"Through our discussions here, they understand that what we were against was the party, not the country and not the people."
On whether China's 20-somethings today will take up the cudgels as he and his peers did 25 years ago, Mr Wang said they "have their ways of caring about the country", whether it was helping out during the 2008 Sichuan earthquake or taking to the streets on environmental issues.
He is optimistic this will broaden into a larger movement over democracy and political reforms, saying that change in China is inevitable.
Countering the argument that certain Asian societies are not suited for democracy, he said the thirst for it is "based on human desires for fairness, equality, and not based on culture".
"China has its problems and it is moving slower, but that doesn't mean it's not headed that way," he said.
"From my perspective, the 1990s-generation care about democracy, they understand it. Perhaps they don't talk about it openly, but that's not their problem, that's the problem of China's system. And I do hope they won't talk about it because that impacts on their safety.
"But it doesn't mean they don't feel it in their hearts."
On his part, he and the others of the 1989 generation, he said, are biding their time.
"China is facing many changes, and we will definitely not be absent at any of these events. So for now, what we are doing is to prepare by enriching ourselves."
The 1989 movement came with its missteps. Infighting among the student leaders and their self-righteousness and unwillingness to compromise when Communist Party general secretary Zhao Ziyang appealed to them to disperse even as he promised to continue a dialogue, some say, helped perpetuate the eventual tragedy.
Mr Wang maintains that he has no regrets about what happened.
"It doesn't mean that we didn't make any mistakes. Such a big- scale student movement can't be perfect. There must be areas for improvement.
"But the emphasis should not be on whether the movement was done well or not, but whether anyone stood up for the cause. And I think that students should care about their country. So, I have no regrets overall. Someone has to do what we did.