"They kill, most often for no reason." ~ Cats don't kill for no reason. They kill because that behavior is part of their niche in the biosphere. Hunt, stalk, kill, eat is what cats do in the wild. The rest of time they sleep. Or they procreate, so there will be more cats to hunt, stalk, kill, eat. From an evolutionary and instinctual point of view their behavior makes perfectly good sense. As pets they can be very loving and cute and adorable in an independent sort of way, but their natural tendency to hunt, stalk, kill, eat has to be controlled, which is why the author's contention that cats should be indoor-only pets is 100% correct.