08/27/2013 05:07 pm ET Updated Oct 27, 2013

What the Conservation Movement Can Learn From Martin Luther King, Jr.

"Let us not wallow in the valley of despair."

I've been thinking of these words this week, as we mark the 50th anniversary of Dr. Martin Luther King Jr.'s "I Have a Dream" speech.

The milestone is an important reminder of how far we have come -- and still have to go -- on the road to racial and social equality. It's also a good time to reflect on the lessons that other movements can learn from Dr. King's leadership.

I'm reminded of a conference I attended in Memphis a few years back. One of the highlights of the trip was visiting the National Civil Rights Museum at the Lorraine Motel, the site of Dr. King's tragic assassination. It was a moving experience.

Seeing the hotel -- exactly as it looked 45 years ago, and still a vivid image in my memory -- I couldn't help but think of all that environmentalists could accomplish if we could generate a similar kind of public passion and conviction that fueled the civil rights movement.

As Michael Shellenberger and Ted Nordhaus have pointed out, Dr. King's "I Have a Dream" speech is famous because of its inspiring, positive vision. How would history have turned out had he given an "I Have a Nightmare" speech instead?

What can we do to build a bigger movement for lasting change? One key, I believe, is to put more emphasis on the positive. A focus on possibilities, and not just problems, reveals that there is hope -- hope for a healthy, thriving planet where nature makes our lives better, safer and more prosperous. And hope for solutions that meet the needs of people while maintaining a healthy natural world. While there will always be some bad actors, most people -- once they understand that their lives and livelihoods depend on healthy natural systems -- will choose to protect the environment. And when people do the right thing, nature can be resilient.

This isn't a call for Pollyannaism. We're not naïve -- the challenges we face are difficult and complex. But the environmental movement needs its own dream around which to rally -- one in which nature and people live in balance, and where everyone can realize their right to a healthy and productive environment.

The environmental movement could also learn from Dr. King's example of seeking common ground on divisive issues. For example, I know from experience that topics like climate change and energy development can bring out the kind of passion that we absolutely need to solve our problems, but also the kind of divisive rhetoric that can get in the way of progress. The challenge in our field is to have calm, respectful conversations with people with whom we do not agree, to understand the basis of those disagreements and to build broad coalitions to move forward. In the words of Dr. King, "We cannot walk alone."

Of course this week's anniversary is also an important time to take a hard look at issues of equality and social justice, and our own roles in making Dr. King's dream a reality. At The Nature Conservancy, for example, we are committed to diversity and valuing differences in everything we do - from hiring the best people to propel our work, to launching projects that meet the needs of diverse communities, to reaching new and diverse audiences to broaden the constituency for conservation. I'll be the first to admit that we still have a long way to go. But there's no time for wallowing in the challenges. As Dr. King so eloquently put it, we must recognize the "fierce urgency of now."

Please click here to view Dr. King's speech.