Jacques Nienaber’s side are red-hot favourites to progress from a rematch of the 2019 final to set up a winner-takes-all showdown with either New Zealand or Argentina.
Flanker Kolisi, his country’s first black captain, overcame childhood poverty to lift the Webb Ellis Cup four years ago in Japan.
The 32-year-old referenced homelessness and unemployment during an impassioned answer to a question about motivation and believes failing to give 100 per cent would be “cheating” his compatriots.
“I don’t think that will ever change, who we play for, who we represent,” he said.
“When you start playing for others and start doing things for other people it’s not easy to give up, it’s much harder.
“When you think of how many people would give anything to be where we are and the majority of the people in our country are unemployed, some don’t have homes.
“For me, giving up and not giving everything would be cheating not just myself and the team but the rest of the people at home.
“The harder we play, the more we do well, the more we are able to open opportunities for others so that also drives us.
“I believe we are a purpose-driven team, we’re not a trophy-driven team; of course the trophies help you to get more people with you.
“Sometimes you can look at the struggles of what you’re going through and feel sorry for yourself. But we use that pain and those struggles and we carry them with us to drive us through the battles. It helps us to keep on going when it’s tough.”
Kolisi will lead out an unchanged team for Saturday’s match against Steve Borthwick’s side at Stade de France in Paris.
“I wish you could see all the supporters back at home,” he continued.
“This is all what people talk about, most of the time, with everything else happening.
“Kids at schools are sending clips of them singing because they know some of us like singing.
“People at work on Fridays wear their green jerseys and the beautiful thing to see is the people who can’t afford the jerseys, they wear anything that’s green, anything that represents the Springboks.
“We see that and that will continuously be our motivation and we know what the team has meant in the past – not just in sport, for our country in general.
“It’s more purposeful when you don’t do something for yourself, only when you are aiding other people that you don’t even know or never even met.”
Underdogs England came into the tournament unfancied but are the competition’s only unbeaten team.
Kolisi insists Borthwick’s men will not be underestimated, despite many pundits and rugby fans feeling a final between the Springboks and the All Blacks is a formality.
“Obviously we don’t see it that way because we know how good England is in the seven previous World Cups that they’ve played,” he said.
“It would be silly to be thinking like that and we’ve never been like that.
“We’ve seen in the World Cup, teams not even in the top 10 beating teams in the top 10 so it would be silly to think like that. We’re not in that mind.
“We know exactly what we’re going to bring and the motivation we have.”
South Africa team: D Willemse; K-L Arendse, J Kriel, D De Allende, C Kolbe; M Libbok, C Reinach; S Kitshoff, B Mbonambi, F Malherbe, E Etzebeth, F Mostert, S Kolisi (capt), P-S Du Toit, D Vermeulen.
Replacements: D Fourie, O Nche, V Koch, RG Snyman, K Smith, F De Klerk, H Pollard, W Le Roux.