My 11th grade English teacher recommended this book in class. I mentioned it to my father and the next day, the book was sitting on the dining room table. More precise and thorough than a thesaurus, this dictionary takes 4 or 5 synonyms for a given entry and describes, sometimes at length, the subtle differences between them. Quotes from literature are invoked to support the arguments. Any synonym that has its own entry is starred, so the reader can literally, and literarily, surf the book forever--much as he would the Internet this book predates.
One only hopes the language doesn't change too quickly.