The aim of this book is to introduce the philosophical thought of Immanuel Kant, especially to readers who are not yet familiar with it. What is most remarkable about the philosophy of Kant, in my opinion,is the wide range of topics on which his thoughts repay carefulstudy. In so many areas - not only in metaphysics but in natural science,history, morality, the critique of taste - he seems to have gone to the rootof the matter, and at least raised for us the fundamental issues, whetheror not we decide in the end that what he said about them is correct. Inhis brief, five-page essay on the question "What is Enlightenment?" forexample, he locates the essence of enlightenment not in learning or thecultivation of our intellectual powers but in the courage and resolve tothink for oneself, to emancipate oneself from tradition, prejudice, andevery form of authority that offers us the comfort and security of lettingsomeone else do our thinking for us. Kant's essay enables us to see thatthe issues raised by the challenge of the Enlightenment are still just asmuch with us as they were in the eighteenth century.