"One of the things that I have learnt from my father and my mother is that these kinds of things - caste, creed, colour and religion... we must rise above these things," the superstar told during a group interaction here.
It is a learning he received from his parents - the late poet Harivanshrai Bachchan and Teji.
"My parents were perhaps a fine example - my father was from Allahabad in Uttar Pradesh and my mother was a Sikh from Punjab. They had an inter-caste marriage - something which was at that time unheard of. But both my parents were strong about this and lived through that," added the 69-year-old.
He still stands by that learning.
"We have never considered any community to be less or more. I have people working in my office, in my own domestic staff, who are from all communities and we never have any discrimination and never treat them differently," he said.
Now he is trying to spread that learning among his fans through the sixth season of hit reality TV game show "Kaun Banega Crorepati" (KBC) that goes on air Sep 7.
In the last season, the KBC campaign centred on the maxim "Koi insaan chhota nahin hota (No man is small)" and brought people from small towns across India to give them a chance to make it big.
This year, Amitabh takes the philosophy forward with "Gyaan hi aapko aapka haq dilaati hai (Only knowledge gets you what you deserve)".
"Nobody is chhota (small)," he said. "Har insaan mein visheshta hota hai (Every person has some uniqueness). No person is small or common. A person may be from a small city. But these days people come from places you haven't even heard of, are making the country proud. So never call anyone small."
In a career spanning over four decades, in which he has travelled the length and breadth of the country, and abroad, the big screen hero has met many thousands.
But meeting real heroes - like last year's winner Sushil Kumar who went from a computer operator earning Rs.6,000 a month to a Rs.5 crore winner - is an experience beyond all.
"The kind of people who come on the show... We knew about them, but never had the opportunity to meet them. And not just meet them, to get to know about their background, their circumstances and what they have gone through to achieve what they do.
"KBC has been a moving experience for me. It has been heartwrenching to hear stories of some of the contestants and you discover that these are our countrymen - and then people want to step in and do something for them. That, for me, is a satisfying experience.
"This is now beyond just a show. It has become a medium where many of such people's facts and circumstances reach not just to you and me but, through the medium of television, to the entire country," Amitabh said.
Knowledge, he believes, will drive social change, and help in evading the pervading gender, economic and caste biases. As he says: "KBC is now not just a game, but it is for those whose lives we can bring a change in."
