This coming Monday in the United States, we’ll celebrate Dr. Martin Luther King Jr., the civil rights leader. Dr. King was an activist, an orator, a thinker, and — as several recent TEDTalks have pointed out — a visionary leader. These three speakers touch on ways in which King’s passionate style galvanized a movement whose time had come.

Midway through her talk at TEDWomen last month, Elizabeth Lesser points to Dr. King as an example of “ubuntu” in action. To define the term, she quotes him: “I can never be what I ought to be until you are what you ought to be.”

In his TEDxPugetSound talk about leadership, Simon Sinek expands on Dr. King’s power of leading others by sharing his own beliefs. The result? “People who believed what he believed took his cause, and they made it their own.”

And Benjamin Zander, in a brief aside during his 2008 TEDTalk, makes a powerful statement: “It’s one of the characteristics of a leader that he not doubt for one moment the capacity of the people he’s leading to realize whatever he’s dreaming. Imagine if Martin Luther King had said, ‘I have a dream. Of course, I’m not sure they’ll be up to it.’”