In contrast to the more theoretical readings 2.1 and 2.2, the author of the third reading, Roger Martin, offers a hands-on approach to using opposing ideas to reach more effective solutions. this recent Harvard Business Review article is drawn from his book The Opposable Mind, in which he argues that the ability to use opposing ideas is the mental equivalent of having an opposable thumb. Without a thumb opposite to our fingers, we would not be able to create the tension in our hands needed to hold things and perform advanced physical activities.