http://www.poochtips.com No conditioned response is infallible. Creatures with advanced brains can think. They can defy conditioning. They also can make mistakes. Think about two of your own conditioned responses. You have a habit of answering the telephone when it rings, but one day you decide not to take any calls. The telephone rings but you keep reading your book. You know what you usually do, but today you decide not to do it. You also have a habit of stopping your car at a red light. But one day you are tired or distracted and you roll through an intersection. Even the most experienced drivers sometimes make mistakes.