John Searle once said that this is the best book on Wittgenstein. I partially agree. I find this book the best introduction to the Tractatus I've ever read, lucid, insightful and clear, and also a good introduction to the late philosophy of Wittgenstein. It is not as scholarly competent as Anthony Kenny's book, which I still find the best introduction to the whole philosophy of Wittgenstein, but it has its own merits, like the independent criticism against the private language argument at the end of the book.