Philosophy: A Very Short Introduction by Edward CraigRead about the other entries on the list.
There are many good short introductions to philosophy but Edward Craig's stands out. No one knows more about philosophy than Craig, who spent decades of his life editing the mammoth Routledge Encyclopedia of Philosophy. And yet he managed to retain the sense of wonder and surprise that academic study can sadly drain out of people. Craig's mind is razor sharp, bright and sparkly.
--Marshal Zeringue