Thomas S. Kuhn wrote this classic work in the early `60's. He sought to describe how scientific revolutions occur. The `60's were famous for numerous social revolutions, most notably in improving the status of blacks and women in our society. Books such as Charles Reich's THE GREENING OF AMERICA rather famously made predictions on the direction of permanent social changes in America that never reached fruition. His book is now in that proverbial "dustbin of history." Kuhn's book is far more notable, and enduring, for providing a paradigm, as it were, on how shifts in scientific perception occur. The "as it were" refers to the fact that Kuhn is credited with first using the phrase "paradigm shift."
Kuhn postulates that there is a model, or paradigm, if you will, called "normal science." Virtually the entire scientific (and even non-scientific) community subscribe to this model. The role of a scientist operating within the normal parameters of a given paradigm is to "tweak" the model; that is, make further advances in our collective knowledge, but within the model's framework. But there always seem to be anomalies to a given explanation of the natural world, and the anomalies can mount, and seem to reach a "critical mass," (itself an expression from another paradigm shift), and eventually the entire paradigm is "shifted" to a new one. Certainly one of the most famous examples, cited by Kuhn, is the revolution in our thinking about our place in the universe, which was led by Galileo and Copernicus. Prior to this revolution, the standard model was that the earth was the center of the universe, with the sun, moon, and all the stars circling it. And they did so in perfect circles, because that is the way God would have wanted it. Perfection. But the observed motion of the celestial bodies mounted, perfect circles were imposed on perfect circles, in an effort to explain the motions, but eventually such structures became unwieldy, and unworkable. The time became right for the "paradigm shift" that stated it was the earth that circled the sun, which was just a small star in a universe full of them. Kuhn cites other examples, notably when Lavoisier published his paper in 1777 on the oxygen theory of combustion, which revolutionized our ideas on chemical processes. Yet another example is the 19th century theory that the universe was composed of "ether" through which waves traveled. That too has been discarded.
Kahn devotes specific chapters to detailing how the anomalies mount to a given paradigm, a "crisis" in scientific thinking occurs, followed by a revolution in that thinking, led by a very few men, and our world view changes, which Kahn declares to be progress. The author quotes Max Planck to sardonically and sadly note how that progress actually occurs: "a new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it." Another enduring quote for me came from Francis Bacon: "Truth emerges more readily from error than confusion."
In the final chapter Kuhn raises, and briefly discusses some still very unanswered questions: "Why should the enterprise sketched above move steadily ahead as, say, art, political theory, or philosophy does not? Why is progress a perquisite reserved almost exclusively for the activities we call science?" "Why should scientific communities be able to reach a firm consensus unattainable in other fields?"
I've read the criticisms of this book which are posted in the Amazon reviews. Certainly one of the most valid is that Kuhn gave very limited coverage to the paradigm shift from Newtonian mechanics to quantum mechanics.
Lastly, I first read this book on the plane back from Vietnam (yes, as in "the war.") I was in desperate need to think about something else, and found it somewhat comforting that in some human enterprise some forward progress was being made. Still, the questions that Kuhn raises at the end of his book remain as valid today as 40 years ago: why progress in science; yet in the political field - and by extension, war , for example, the same old stupid mistakes continue to be made over and over again. Kuhn's work remains a five-star read, and I am pleased to see that as of this posting, his book is in the top 1000 best sellers.