Book excerpt: O. K. Bouwsma, one of America's foremost Wittgensteinians, was also an extraordinarily dedicated and effective teacher. The present collection, assembled posthumously from his papers, includes twelve essays, all but one previously unpublishedøand all characterized by the humor, common sense, and wisdom that marked his classroom lectures. Ranging in subject matter from topics in Wittgenstein to Descartes to aesthetics, the pieces all show the influence of Wittgenstein. Some of the questions they raise deal with the traditional and historical background of twentieth-century philosophy?"Am I dreaming?" "Is what I see real?" "Are there material objects?"?while others relate to considerations peculiar to thinkers today, for example, "What is Wittgenstein doing in his writing?" "What does philosophy have to do with language?" Bouwsma wants first to understand the philosophical questions?to unknit the knit eyebrows it produces. Accordingly, his major concern is how we as thinkers, readers, writers, and speakers, separate what we understand from what we do not understand: hence his consideration, in the opening essay, of "a new sensibility in the matter of our language." Always approaching the subject as a practical problem rather than as an abstract, theoretical issue, these essays demonstrate, with patience and wit, ways to achieve clarity on puzzles long thought intractable.