books.google.com.au - "A wheel turns because of its encounter with the surface of the road; spinning in the air it goes nowhere. Rubbing two sticks together produces heat and light; one stick alone is just a stick. In both cases, it is friction that produces movement, action, effect. Challenging the widespread view that globalization...http://books.google.com.au/books/about/Friction.html?id=0w32dvoW0aEC&utm_source=gb-gplus-shareFriction
