After his wife died, Elzéard Bouffier decided to cultivate a forest in a desolate, treeless valley. He built small dams along the side of the nearby mountain, thus creating new streams that ran down into the valley. Then, he planted one seed at a time.

After four decades of steady work, the valley throbbed with life. You could hear the buzzing of bees and the tweeting of birds. Thousands of people moved to the valley to enjoy nature at its finest. The government assumed the regrowth was a strange natural phenomenon, and the valley's inhabitants were unaware that their happiness was due to the selfless deeds of one man.

This is The Man Who Planted Trees, a popular inspirational tale.

But it's not just a tale. Abdul Kareem cultivated a forest on a once-desolate stretch of 32 acres along India's West Coast, planting one seed at a time. It took him only twenty years.

Like trees in the ground, rationality does not grow in the mind overnight. Cultivating rationality requires care and persistence, and there are many obstacles. You probably won't bring someone from average (ir)rationality to technical rationality in a fortnight. But you can plant seeds.

You can politely ask rationalist questions when someone says something irrational. Don't forget to smile!

You can write letters to the editor of your local newspaper to correct faulty reasoning.

You can visit random blogs, find an error in reasoning, offer a polite correction, and link back to a few relevant Less Wrong posts.

One person planting seeds of rationality can make a difference, and we can do even better if we organize. An organization called Trees for the Future has helped thousands of families in thousands of villages to plant more than 50 million trees around the world. And when it comes to rationality, we can plant more seeds if we, for example, support the spread of critical thinking classes in schools.

Do you want to collaborate with others to help spread rationality on a mass scale?

You don't even need to figure out how to do it. Just contact leaders who already know what to do, and volunteer your time and energy.

Email the Foundation for Critical Thinking and say, "How can I help?" Email Louie Helm and sign up for the Singularity Institute Volunteer Network.

Change does not happen when people gather to talk about how much they suffer from akrasia. Change happens when lots of individuals organize to make change happen.