AC Grayling, who is a supremely rational and talented philosopher and essayist, has in this little book laid out the basic ideas of Wittgenstein's philosophy, and has clearly demonstrated that they do not make sense. Wittgenstein is accused of anti-realism (he is vague about whether there is an external reality independent of thought and language) and of cognitive relativism (different communities may experience different truths and realities). So, Mr. Wittgenstein, who in the popular mind is a genius of philosophy, is in reality a paragon of irrationality rivaling Derrida or Foucault. Thanks to Grayling, I will never again trouble myself to wonder whether it would be worth the effort to study Wittgenstein. Thank you, AC, for this nice little book.