Stewart Brand On Colbert (VIDEO): Is Nuclear Power Green 'Because That's The Color We'll Glow?'

Stewart Brand has been around since right around the inception of the environmental movement. He's best known for the Whole Earth Catalog, published between 1968 and 1972, which listed thousands of tips and products for leading a sustainable life, ushering in an alternative lifestyle that forgoes the "system" and emphasizes a DIY mentality.

Brand has since renounced some of his old idealism, trading it in for what he calls ecopragmatism. Brand appeared on The Colbert Report to discuss his new book, Whole Earth Discipline: An Ecopragmatist Manifesto, and why he thinks nuclear power is the way to get us off fossil fuels.

"Thirty years ago, the environmental movement sort of decided some things, and it hasn't changed much since, and the world's changed a lot," Brand said. "So I think now that cities are green, nuclear power is green, genetically-engineered crops are green..."

"Wait," Colbert cuts him off. "Nuclear power is green? Why, cause that's the color we'll eventually glow?"

Brand argues that nuclear doesn't put out as much greenhouse gases as coal, making it a good alternative.

"But, you used to be against nukes," Colbert points out.

What changed?

WATCH Brand make his argument on nuclear power, oil, and "clean" coal: