In                       the modern world, science and society often interact in                       a perverse way. We live in a technological society, and                       technology causes political problems. The politicians and                       the public expect science to provide answers to the problems.                       Scientific experts are paid and encouraged to provide answers.                       The public does not have much use for a scientist who says, “Sorry,                       but we don’t know”. The public prefers to listen                       to scientists who give confident answers to questions and                       make confident predictions of what will happen as a result                       of human activities. So it happens that the experts who                       talk publicly about politically contentious questions tend                       to speak more clearly than they think. They make confident                       predictions about the future, and end up believing their                       own predictions. Their predictions become dogmas which                       they do not question. The public is led to believe that                       the fashionable scientific dogmas are true, and it may                       sometimes happen that they are wrong. That is why heretics                       who question the dogmas are needed. 
As a scientist I do not have much faith in predictions. Science                     is organized unpredictability. The best scientists like to                     arrange things in an experiment to be as unpredictable as                     possible, and then they do the experiment to see what will                     happen. You might say that if something is predictable then                     it is not science. When I make predictions, I am not speaking                     as a scientist. I am speaking as a story-teller, and my predictions                     are science-fiction rather than science. The predictions                     of science-fiction writers are notoriously inaccurate. Their                     purpose is to imagine what might happen rather than to describe                     what will happen. I will be telling stories that challenge                     the prevailing dogmas of today. The prevailing dogmas may                     be right, but they still need to be challenged. I am proud                     to be a heretic. The world always needs heretics to challenge                     the prevailing orthodoxies. Since I am heretic, I am accustomed                     to being in the minority. If I could persuade everyone to                     agree with me, I would not be a heretic.
These thoughts are those of FREEMAN DYSON, a professor of physics at the Institute for Advanced Study, in Princeton. They are especially worthy of consideration when reading the lay press describe the effects of global warming in 25 to 100 years. The book is HERETICAL                               THOUGHTS ABOUT SCIENCE AND SOCIETY.