"What are these young people thinking?" is perhaps the most asked question from those old enough to be their parents.

With youth unemployment at more than double the overall rate and fewer than one-fifth of local students able to get into publicly funded university programmes, some have concluded that the youth are "angry" simply because it is getting harder to move up the social ladder. They rebel because they can't find a way to get the jobs and education that would provide them the money they want, goes this line of thinking.

But such thinking is obsolete, said Professor Wu Xiaogang, who heads the Centre for Applied Social and Economic Research at the University of Science and Technology. "They are two distinctly different groups - those who choose the path of social activism and those whose major cause of worry is how to get ahead in a career," he said.

Unlike the previous generation, those born after 1980 are more willing to stand up for social issues that do not directly affect them, he said, as witnessed in the protest against new towns in which most participants will not see their homes razed no matter how the debate ends.

"Many of them [today's social activists] come from a middle-class background themselves, which is why they can go to university in the first place," he said, adding that achieving upward mobility in the traditional sense may not even be high on their agenda compared with fighting for social justice or living the lifestyle they want.

"Those in power are still fixated on the notion that all young people want is getting pay rises and owning cars and properties, because to them that's the only definition of upward mobility," said Liu Sze-ming, 25, who helped organise this year's July 1 march.

"But our generation is asking whether this is the only way of life, whether we will be losing more even if we are making more money."

That is why urban development projects in recent years have faced such strong opposition from young activists, Liu said, pointing out that many in his generation want to put an end to the kind of building that benefits mostly the rich and powerful at the expense of ordinary folks.

Hong Kong's social movements had always been led by political parties or unions until the campaigns in 2006 and 2007 against the demolition of the Star Ferry pier in Central and the nearby Queen's Pier.

Despite their failed attempts to save them, the young activists - collectively known as the post-80s generation as most were born after 1980 - have emerged from those demonstrations as a force to be reckoned with.

In recent years, it has mostly been the younger activists who have led mass protests in the city, from the 2010 campaign against the cross-border high-speed railway and the rallies against the compulsory national education curriculum in 2012 to the recent fight against the northeast New Territories new towns.

Just as with social movements elsewhere, the young activists in Hong Kong might be the most vocal but they are also in the minority, even within their age group, said Brian Fong Chi-hang, assistant professor at the Department of Asian and Policy Studies at the Hong Kong Institute of Education. "Many of my students are planning to join the civil service, even though none of them think highly of Beijing or the Hong Kong government," he said.

What he terms the progressive force in Hong Kong now counts between 20 and 30 per cent of the population as members. This, he said, passed the threshold of a "critical mass" a few years ago.

"Today, there exist two Hong Kongs - one progressive and the other conservative," Fong said, before adding that in his estimation conservatives still account for half of the city's population.

He said today's young and progressively minded, unlike their predecessors, never believed they could achieve genuine democracy if they abided by rules set by Beijing. This explained why many saw social activism as a way to make a difference.

The often loosely organised activist groups such as Scholarism mobilised their supporters on social media and had been and would continue to be a headache for the government due to their unpredictable nature, he said. "The government was always dealing with the same group of people [in the past] and both were willing to make deals since they have a long-term working relationship to keep … but now, it's hard enough even identifying who [the government] is going to deal with."

Both academics agree the young successors to the leadership of the city's social movements need to present their own vision for the way forward backed up by research by local scholars, similar to what young activists in Taiwan have done. Social movements there first emerged during the pre-war period against Japanese colonial rule. Apart from taking to the street, the major opposition in Taiwan, which calls for the island's independence, has developed its own rationale backed up by academic research on why Taiwan should not be considered part of China.

Assuming Beijing in the end refuses to grant Hong Kong "genuine" democracy, Fong said the progressives "will be obliged to present their own narrative on the way forward if they think real democracy under the 'one country, two systems' model proves to be a lie. Revolution is not possible in reality."

A Hong Kong separate from China: the dream driving radical Billy Chiu

A notable figure among the relatively young activists is Billy Chiu Hin-chung, 29, whose political beliefs are more extreme than those of most radical democrats in the city.

A former member of the League of Social Democrats, Chiu quit after a brief stint in 2012. He said the break-up was due to "a certain degree of difference" of opinion. After resigning, he founded at the start of last year Hongkongnese Priority, a group that strives for more autonomy for the city.

He said the other pan-democratic groups "believe in the notion of a Greater China", meaning that all Han Chinese fall racially into the same group. "But I think Hong Kong should be separated from China," Chiu said.

He said that since Hong Kong was annexed by the Qing dynasty (1644-1911), it should be returned to it, not to the government in Beijing.

Chiu, who used to work as a bartender and clerk, said he had seen many attempts by Hong Kong's government to act as if the city and the mainland were not separate places.

"We are slightly different from the mainland because of our political system and culture, which includes our language," he said. [These differences] can be retained now because of this thin border. If the border disappeared our political system would be gone and our identity lost."

He said his political awakening came after he noticed people starting to speak out against mainland influence.

Despite being almost jailed for breaking into the PLA barracks in Central - which he said was his symbolic way of protesting - Chiu said he would continue the political fight until the day Hong Kong had full autonomy.

We're missing bigger picture, trainee teacher says, but education can help

"Education in Hong Kong teaches us nothing other than how to succeed in exams in the hope of securing a good job afterwards," said Liu Sze-ming, who helped organise this year's July 1 march.

A desire to "make a change" in the education system is what motivates the 25-year-old's activism and his plans to become a primary-school teacher.

"What we learn at school is very much disconnected from our own lives," said the final-year student at the Hong Kong Institute of Education, as he removed batteries from loudspeakers two days after the march.

Liu, like many other young activists, saw the 2010 campaign against the cross-border railway as an eye-opener. It led him to become more politically involved.

"Even if you'd farmed only once in your life, you would understand how closely man is connected to land, and you'd realise the high-speed railway destroys not only the farmland" but a way of life, Liu said.

"Social movements should not limit themselves to development issues or political reform," he said. "Even universal suffrage won't make our society a just one all of a sudden. There is a lot of work to be done in the meantime."

He said society needed to change its thinking.

"We're too accustomed to personalising the problem, while failing to see what's wrong at the institutional level," he said, citing Taiwan, which has undertaken a lot of soul-searching since student Cheng Che, 21, killed four passengers in a stabbing spree in a Taipei subway in May.

He says his family has been supportive of his political activism. "My father told me: 'If that's what you've chosen to do, do it well.' "

Ma Jai's social activism inspired by his pastor dad taking him to protests

When asked how many times he has been arrested during his four years as a social activist, 20-year-old Ma Wan-kei, better known as Ma Jai, needed to pause for a minute and count.

"Arrested eight times, charged five times and convicted three times," said Ma, adding that three of the arrests took place before he was 18.

He has been convicted and fined for illegal assembly twice, and once for blocking a motorway.

The young activist, who until recently sported a head of hair in the style of lawmaker "Long Hair" Leung Kwok-hung, decided to drop out of school at the age of 16 after worse-than-expected public exam results.

He attributed his low score to his part in the 2010 protests against the cross-border express railway, which took place when others were busy studying for the tests.

A year later, he began working full-time in Leung's League of Social Democrats office. Ma credits his pastor father, who had taken him to the city's major protests since he was a child, for being the main inspiration behind his social activism.

"It all started with the righteous indignation which I felt about how society is run," Ma said.

"You have to be ready to accept the fact that for all the hard work, you're perhaps only a few inches closer to your target than before."

But it is the progress, albeit slow, together with support from his comrades, that has sustained him in this long fight. "I still have hope for Hong Kong," Ma said.