I’ve been “doing” social change for 50 years. The tools and tactics have changed—from marching in the street to reaching out with social media—but the basic principles persist. Winning hearts and minds takes vision, leadership, clear goals powerfully communicated, innovative programs, and lots of people.

On November 5, 1962, the Reverend Martin Luther King Jr. visited the University of Michigan. It was a dramatic time. The world teetered on the brink of nuclear madness in the Cuban Missile Crisis. Federal troops were on patrol after the first black student was admitted to Ole Miss. And Bob Dylan was singin’ “A Hard Rain’s a-Gonna Fall.”

I was a solipsistic sophomore, locked in my own selfish bubble. But when the Rev. King spoke so powerfully that day of a life of service to social justice, a small group of us sat around him for hours, mesmerized. We all signed up for the cause. We marched in Selma, Ala. and Mississippi and Washington, D.C., for freedom, social change, and civil rights. We marched against secret wars in Southeast Asia.

We won some and lost some, but we stopped the Vietnam War and passed the Voting and Civil Rights Acts. Few of us had the vision to perceive the global drama unfolding around the world in the same way that the Rev. King did when he said, “The arc of the moral universe is long, but it bends toward justice.” We tilled our corner of the global garden.

Over time, however, social change organizations began to evolve. They were better run, best practices were shared, communities of excellence arose, and leadership was recognized. The most innovative leaders were christened “social entrepreneurs.” People like Klaus and Hilde Schwab of the Schwab Foundation for Social Entrepreneurs, Bill Drayton of Ashoka, and Sally Osberg, who led our sister organization the Skoll Foundation, pioneered the field of social entrepreneurship.

Social entrepreneurs aren’t traditional activists. They don’t often drive millions of people to the streets, but they do seek to create social change that can scale up. Scale is what separates good from great, the well-intended from the truly transformative. I tasted the raw power of scale in marches in the 1960s, but working on the smallpox program in South Asia in the 1970s taught me the power of combining scale and focus. To eradicate smallpox, we had to find and contain every outbreak in the world, search every home for hidden disease. In India, we made more than 1 billion “house calls,” with an army of 150,000 public health workers and volunteers. We didn’t march against smallpox, but we put feet on the street to conquer this horrible disease.

In 1979, I co-founded the Seva Foundation to restore sight to poor blind people. Seva was social entrepreneurial before the term was widely known. Its innovative premise was that “appropriate technology” was technology that poor people could afford. By driving the price of a sight-restoring operation to (then) $5, we could deliver service on a large scale to anyone in the world. Seva and our beloved partner, the Aravind Eye Hospital, have restored sight to more than 3 million people.

Social change is participatory. That’s what makes it social. It has always required intellectual and moral catalysts. But lasting change happens by engaging and affecting large numbers of people. Today, scale comes from connectivity. With mobile phones, the Internet, and social media, the tools of social change now allow us to reach billions of people.

Social change is participatory. That’s what makes it social. It has always required intellectual and moral catalysts. But lasting change happens by engaging and affecting large numbers of people.

When Steve Jobs started Apple, his views were informed by the 1960s; he wanted to bring “power to the people” by putting computing power on every desktop. Drayton likes to say “everyone a changemaker.” I think of social change today as a little Bill Drayton mixed with a touch of Steve Jobs; a heady brew to scale up social change. Combining technology with changemakers drives change, whether we use mimeograph machines in the Civil Rights Movement or Twitter and Facebook in the Arab Spring.

Connectivity drives change. Ironically, the newest technology can be an antidote to existential threats brought about by modernity: climate change, pandemics, nuclear proliferation, water security, and regional conflicts like the Middle East that can rapidly become global wars. The Skoll Global Threats Fund was created by Jeff Skoll to combat these global threats. These great challenges cannot be met without planet-wide connectivity, participation, and the most effective innovations.

Whether you fight for animal or human rights, work on poor eyesight or mental illness, challenge the government for wrongs local or global, seek to lessen the burden on the poor, or battle to bring water, health care, and education to those who need it, you are a changemaker, part of the warp and weft of social change. Social change is far more than technology and longer than a 50-year story. Trying to improve our children’s future is as old as history. We engage in it because we are activists and, deep inside, optimists. The Rev. King wasn’t saying that changemakers could sit back and passively observe the arc of history bending toward justice; his life was a call for us, the changemakers, to act, to leap up to that arc, wrap our arms around it, twist it and pull it down, bending it toward justice.

This is the part of “doing” social change that we have signed up for.