Coffa's tracking of the history of the search for 'meaning' in philosophy (as opposed to the search for meaning), remained sadly unfinished before his death. The early chapters on Kant, unfortunately, I found extremely muddled and confusing, which is why I can't rate this book five stars. The later chapters on Carnap and his contemporaries, however, offer superb and careful explication and scholarship. A flawed book but worthwhile investigating.