William James´s strong beliefs in a pragmatic theory of truth - that truth is only as relevant as its effect on us - lead to these absorbing essays on fact and belief. Within them is a fascinating theory of reality that suggests nothing is truly ´real´ without examination through human empathy and experience. Throughout history, some books have changed the world. They have transformed the way we see ourselves - and each other. They have inspired debate, dissent, war and revolution. They have enlightened, outraged, provoked and comforted. They have enriched lives - and destroyed them. Now Penguin brings you the works of the great thinkers, pioneers, radicals and visionaries whose ideas shook civilization and helped make us who we are.