Well over six-feet-tall and with flowing white hair, Senator Moynihan was an imposing figure. Witty and quick to smile, erudite and well-spoken, he filled a room. And now, he had me in his spell. It was his intense gaze, his aura that did it. His eyes locked onto mine. The room blurred. I was entranced. He turned back to the audience.

“This man has come all the way from Mississippi to tell us about zebra mussels. We must give him our attention.”

I had not expected such a formal introduction. Our eyes met again.

Now I was the most important person in the room. He had transferred some of his prestige, the power of his position, to me. He had given me an order, a task that only I could complete. I could not let him down.

It was early summer, 1991, and I was at a Town Hall Meeting in upstate New York. The subject was zebra mussels (Dreissena polymorpha), an invasive mollusk not much longer than a thumbnail. After these bivalves were first found in Lake St. Clair, Michigan in 1988, they quickly spread east where they clogged water pipes and fouled intake screens in hydropower and water pumping facilities along major waterbodies. Several months before this meeting, scientists discovered zebra mussels in the Hudson River. Facility operators were concerned that they could spread into the New York City water supply system. Since females produce millions of eggs and both sexes mature early, the time between detection and full infestation could be less than a year.

I had learned about my assignment two days earlier. “Am I supposed to give a presentation?” I asked my point of contact.

“Nothing like that,” he said, “Just be there to answer questions. Senator Moynihan wants to let the locals know he’s aware of the problem and is ready to help.”

Two days later, I was in the front of a full auditorium, seated at a long table with the senator, several of his aids, and a handful of local officials. A presentation. I glanced at my notepad. It was blank except for the date, location of the meeting, and names of those at the table. The room was silent. Every eye was upon me.

I thanked him, took a deep breath, and dove into an impromptu discourse on zebra mussels: their biology and ecology, how they spread, their current distribution, how they were accidently brought to this country from Europe in the ballast water of an ocean-going vessel. I finished by listing control strategies and methods. My presentation lasted less than ten minutes.

When the meeting was over, we rode back to the helicopter that would carry us to LaGuardia Airport. I still reeled from my experience. If Moynihan had asked, I would have done anything for him. Nearly 30 years later, I still remember how he captured me with his gaze.

As we were about to board the helicopter, I watched him do it again, this time to a line of State Police at the edge of the tarmac. He stopped, gave them a combination salute and wave, tipped his head forward, met their eyes with his. No words were spoken: his body language said it all: Thank you for your service; you are the best of the best. He had made them indispensable, they were on his team. They were proud to serve, willing to do whatever he asked.

What is it about some people—the Senator, Mahatma Gandhi, Eleanor Roosevelt, Martin Luther King, Jr., Oprah Winfrey—that gives them this ability to mesmerize and influence? Some are physically attractive, but they don’t have to be. And, it’s more than making people feel important; typically, they also exhibit exemplary grace, kindness, and the ability to connect. Oprah Winfrey, with her interest in literature, self-improvement, and spirituality, could relate to millions. Martin Luther King, Jr., distilled and expressed the views of men and women everywhere, regardless of race, with a clear, understandable message. But magnetic leaders don’t do it all on their own. They would be nothing without their devotees. Their words must resonate and attract attention. Eleanor Roosevelt and Mahatma Gandhi had messages that riveted, but their impact would have been lost if they had not fallen on receptive ears. We don’t follow unless we’re convinced by their message.

Being unduly influenced by others can be dangerous. Over 900 of Jim Jones’s supporters committed suicide or were murdered; 39 members of the Heaven’s Gate religious group, led by Marshall Applewhite, also killed themselves. Uncritical adherence to any position could have negative consequences. Eloquent, well-meaning spokespersons bombard us with their assessments on genetically engineered products, vaccinations, abortion, sex education. Before we accept their ideas, do we examine the long-term implications of their views?

Senator Moynihan’s ability to seduce gave me pause. Could I be captivated by someone like Jim Jones or Marshall Applewhite? After all, I was awe-struck by the senator. He and I agreed on a very mundane issue that I had studied for years: the need to understand and control an invasive species. What about a religious zealot or someone opposed to vaccinations? Could I fall under their spell? I hope not.

Society has always had its persuasive leaders. Sometimes they push us forward, sometimes they hold us back. Regardless, at some level, we decide whom to follow. As I discovered at the meeting with Senator Moynihan, it’s easy to be swayed by charisma. But we must be responsible. We need to critically evaluate the message, not just be influenced by the messenger.