Bryan Magee's 'Introduction to Western Philosophy' is a brilliant analysis of the works of the most important Western philosophers from Plato to Bertrand Russell.
This book is based on a BBC TV series which was presented as a discussion between the author and one of the leading authorities on every philosopher.
During the discussions all the most important philosophical problems were tackled. To name a few: causality, determinism, free will, freedom, the existence of the self, the body-mind problem, the subject-object relationship, the problem of induction, tolerance, the problem of the just war or the basics of human nature ('the would-be knower is a biological organism struggling for survival').
This book is written in very clear, straightforward and very comprehensive prose, rather exceptional for this kind of work.
It gives a magisterial summary of the basic ideas of every philosopher. Into the bargain, it can be consulted easily for every chapter can be read independently.
I have only a few remarks. First, I miss one great philosopher of the 20th century: Karl Popper. I suppose that he was left out because he was still living when the book was published. On the other hand, Bryan Magee filled the gap by writing a separate book on Popper, which I recommend to everyone.
Secondly, I don't share his enthusiasm for the 'second' Wittgenstein and the latter's disastrous sliding into the morass of linguistics with his language games.
All in all, this book is a magisterial summary of 2500 years of Western philosophy. A must read.