"In China's history of more than 3,000 years, there were other leaders who tried to use their own thoughts to regulate the thoughts of others," he said in an interview in his modest Beijing apartment. "But none were successful. There were only failed attempts."
Bao was the most senior Communist Party official to be incarcerated for sympathizing with the 1989 Tiananmen Square protests, thrown into jail May 28, a week before a military crackdown that left hundreds if not thousands dead.
He was to remain in solitary confinement for seven years, and even today lives under constant surveillance, he said, with three agents following him on foot and others in a car whenever he leaves his home. Yet he still manages an occasional interview with the foreign media, his manner affable, his opinions trenchant, and with a cigarette never far from his lips.
In the late 1980s, Bao had worked as a top aide to Communist Party General Secretary Zhao Ziyang, helping push China in a more liberal, reformist direction — until the June 4 crackdown ended that dream. Zhao was demoted, purged and placed under house arrest for expressing sympathy for the students' demands and opposing Deng Xiaoping's decision to send in the troops.
Bao was thrown into Beijing's maximum security Qincheng Prison, a destination for many of the nation's most important political prisoners.
Today, a photograph of Zhao sits proudly on a shelf in his apartment, and he talks affectionately of a man who "treated everyone as equals" and wanted to turn over decision-making power from the party to the people.
There is no such affection in his comments about President Xi, whom he describes as a "hard-liner" and a throwback to Mao Zedong.
Last month, the Communist Party enshrined Xi's name in its constitution as it granted him five more years in power: Xi Jinping Thought now sits alongside Mao Zedong Thought and Deng Xiaoping Theory in the party's ideological canon.
"It is called Xi Jinping Thought, the new thought, but they are just old ideas, not new ideas," said Bao. "Ideas like 'the party leads everything' — they are exact quotes from Mao Zedong. Why call them new ideas?"
Bao knows only too well the madness that can be unleashed when one man rises to absolute power over the Chinese people, and when officials are too scared to tell him when he is wrong.
"The mistakes Mao made were all huge," he said. "Mao didn't recognize his mistake when the Great Leap Forward led to a famine that caused millions of deaths; he didn't recognize his mistake in the Cultural Revolution in which tens of millions were purged."
In 1966, only days after the beginning of the Cultural Revolution, Bao, who was working as a bureaucrat, was denounced as a "capitalist roader."
Barred from his office, he spent a year cleaning toilets, another year doing hard labor in a re-education camp and the better part of a decade working the fields of rural China. He was only rehabilitated, like millions of others, after Mao's death in 1976.
"There was only one slogan at that time — 'Down with anyone who opposes Chairman Mao,' " he said. "But in the end Mao failed, too. He failed so badly his wife was labeled a counterrevolutionary, and so he himself became part of a counterrevolutionary family."
Mao's widow Jiang Qing was arrested after his death for her role in the Cultural Revolution and sentenced to life imprisonment, finally committing suicide in 1991.
Bao also draws lessons from much further back in his nation's history to warn of the dangers of unchecked power, starting with King Li of the Zhou dynasty, who ruled in the 9th century B.C. The General History of China, an 18th-century text by French Jesuit historian Jean-Baptiste Du Halde, describes Li as proud, conceited and cruel.
Indeed, so conscious was he of how much he was hated, he supposedly forbade his subjects "on pain of death to converse together, or even whisper to one another," Du Halde wrote, so that people could be seen walking the streets with downcast eyes, "in mournful silence."
Eventually, peasants and soldiers rose up against Li, and he died in exile.
Emperor Qin Shi Huang is remembered as the first ruler of a united China in the 3rd century B.C., and for his mausoleum guarded by the Terracotta Army, but he also allegedly banned and burned books, and executed scholars.
The Hongwu Emperor, who established the Ming dynasty in the 14th century, expected total obedience from his subjects, inflicting torture and death on those who opposed him, including, it is said, some of his own advisers.
But in the end, Bao said, these rulers' dynasties foundered and were overthrown.
"If you want to imitate Chairman Mao, that's okay, but the problem is whether you will succeed," Bao said, referring to Xi. "I can't say whether his attempt will succeed or not. Only time will tell."
Bao blames Deng for ending the dream of political change in China, and for instigating an era of corruption and growing economic inequality that "broke" Chinese society.
But he has no faith in Xi's anti-corruption campaign, which the government says has led to some form of punishment for more than a million officials.
"It's a selective anti-corruption campaign. Its nature is the selective protection of corruption," he said. "When you purge some corrupt officials, you are protecting the others. You protect the corrupt system, and you protect corrupt people who support you."
Bao was one of the first signatories of Charter 08, a manifesto for democratic changes issued in late 2008. The only way to fight corruption properly, he says, is for independent supervision of the effort.
"Power tends to corrupt," he said, quoting Britain's Lord Acton, "and absolute power corrupts absolutely."
Luna Lin contributed to this report.