For commencement speakers, a message of “changing the world” almost seems mandatory to include.

At Colorado College on Sunday, Oprah Winfrey told graduates that “you have to act as if it were possible to radically change the world. And you have to do it all the time.” In her famous 2011 Barnard College graduation speech, Facebook chief operating officer Sheryl Sandberg asked students: “What in the world needs to change, and what part do you plan on playing in changing it?”

And in his 2014 commencement address, Adm. William H. McRaven memorably told graduates at the University of Texas at Austin that “to change the world, start off by making your bed,” and then reminded graduates of the multiplier effect: “If every one of you changed the lives of just 10 people — and each one of those folks changed the lives of another 10 people — just 10 — then in five generations — 125 years — the class of 2014 will have changed the lives of 800 million people.”

There is nothing wrong with any of these calls for good deeds, and these speakers have made their own impact on the world. But listening to such advice and actually putting it into action — as graduates of Morehouse College watched billionaire Robert F. Smith do Sunday when he said his family would eliminate their student loan debt — has the potential for profoundly different outcomes.

Not only did Smith show the power of taking action for Morehouse’s students, offering an example of what they, too, could do for others if they also built successful careers upon the foundation of their degrees, but he also called for graduates and alumni to follow in his footsteps, doing their own part to literally pay it forward for another graduating class.

“On behalf of the eight generations of my family who have been in this country, we’re going to put a little fuel in your bus,” Smith said to the graduates. “This is the challenge to you, alumni. This is my class — 2019. And my family is making a grant to eliminate their student loans.”

After the cheers and applause and chants subsided, he went on: “Now, I know my class will make sure they pay this forward. And I want my class to look at these [alumni], these beautiful Morehouse brothers, and let’s make sure every class has the same opportunity going forward — because we are enough to take care of our own community.” Estimates of the value of the gift have varied, with some reports putting it in the $10 million range while others have said as much as $40 million.

Graduation speeches are intended, of course, to provide inspiration that launches fresh minds into the world. Some of the best speeches have reminded graduates of the power of failure, encouraged them not to waste time “living someone else’s life,” or thoughtfully described how to pay attention to what matters and think about the people around us.

But even memorable admonitions to “stay hungry, stay foolish,” or anecdotal stories of how speakers managed their own lives and careers, don’t carry the same weight as witnessing actions such as Smith’s. His gift has the potential to provide, in real time, with real consequences, an example to graduates of the multiplier effect McRaven described.

Without student loan debt, these graduates can choose different career paths with less concern about the accompanying salary, going into careers or working in fields that do more good for the world. With less debt, they may be better positioned to launch new businesses that create more jobs. And they can invest more of their wages into long-term investments or use the money that would have gone to pay off loans to help family members, both of which could have profound effects in changing the trajectories of their families’ or their communities’ lives.

There were signs that the speech was already having that effect. Morehouse graduate Dwytt Lewis told CBS News that Smith’s gift would wipe away $150,000 in debt, saying, “I’m so motivated to go change the world.” The 21-year-old, who said he comes from Compton, Calif., and used to be homeless, said the power of someone saying his loan burden was being taken care of in his “last 30 seconds of being an undergrad student” was inspiring him to help others.

“I think once you have that mind-set of ‘I want to be impactful and I want to change the world,’ " he said, “I promise you that energy just transpires.”

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