Memering, Dean and William Palmer, eds. Discovering Arguments: An Introduction to Critical Thinking and Writing with Readings. Upper Saddle River, NJ: Prentice Hall, 2002.

In The Seven Habits of Highly Effective People,Stephen Covey discusses "paradigm shifts" in reasoning. A "paradigm" is a pattern, a standard theory or explanation about some aspect of reality. When you throw a baseball up into the air, you have a "paradigm" about what will happen to the ball. Should the ball for some reason not come down, and then all balls thrown into the air not come down as you expect (as if gravity had been turned off), it would mean that an important part of your understanding about reality was wrong! Your standard paradigm about baseballs in the air would have shifted.