Her intentions are good, and her information is bad - a prescription for disaster

From State of Fear by Michael Crichton. Page 482.

"You're playing with words."

"Hardly. Is changing the world to suit one's purposes unnatural?"

"Of course. It is interfering with nature."

"Ever seen a termite mound? A beaver dam? Those creatures change the environment dramatically, affecting many other creatures. Are they interfering with nature?"

"The world is not in danger," she said, "from termite mounds."

"Arguably it is. The total weight of termites exceeds the total weight of all the humans in the world. A thousand times greater, in fact. Do you know how much methane termites produce? And methane is a more potent greenhouse gas than carbon dioxide."

"I can't continue this," Ann said. "You enjoy arguing. I don't. I just want to make the world a better place. I'm going to go read a magazine now." She went to the front of the plane and sat down, her back to Kenner.

Sarah stayed where she was. "Her intentions are good," she said.

"And her information is bad," Kenner said. "A prescription for disaster."

[snip]

"I think you're being harsh," Bradley said, in his presidential tone. "Why should you call someone like Ann a prescription for disaster?' She cares very much about these issues. She has devoted her life to them, really. She cares."

"So what?" Kenner said. "Caring is irrelevant. Desire to do good is irrelevant. All that counts is knowledge and results. She doesn't have the knowledge and, worse, she doesn't know it. Human beings don't know how to do the things she believes ought to be done."