“Intelligent life on other planets? I'm not even sure there is on earth!”

“Personally, I don’t think there's intelligent life on other planets. Why should other planets be any different from this one?”

“I'm sure the universe is full of intelligent life. It's just been too intelligent to come here.”

“If there’s life on other planets, then the earth is the Universe’s insane asylum.”

“Some molecules - ammonia, carbon dioxide, water - show up everywhere in the universe, whether life is present or not. But others pop up especially in the presence of life itself. Among the biomarkers in Earth's atmosphere are ozone-destroying chlorofluorocarbons from aerosol sprays, vapor from mineral solvents, escaped coolants from refrigerators and air conditioners, and smog from the burning of fossil fuels. No other way to read that list: sure signs of the absence of intelligence.”

“Surely she had endured enough for one evening without having to listen to intelligent conversation?”