from Nat'l Catholic Reporter: ...Ratzinger closed his chat with an uncharacteristic personal touch. He confessed, as friends and students already knew, that he is a cat lover. Noting that the book on Opus Dei has a small chapter entitled the “invisible cat,” he joked that he was especially pleased with that section. (The reference, by the way, is to a phrase of C.S. Lewis in The Four Loves about the danger of assuming the existence of something despite the absence of proof, like an invisible cat on the sofa. The author, Romano, uses Lewis’ concept to refute the idea that Opus has a political agenda).