For philosophical ideas and problems confront us like geological specimens in situ; and, in the act of prising them free from their historical and cultural locations, we can too easily forget about the matrix in which they took shape, and end by impossing on them a sculptural form of our own making. Something of this kind has happened in the case of Ludwig Wittgen­ stein. For his philosophical work has commonly been seen as an episode in the development, either of mathematicallogic, or oftwentieth-century British philosophy. His associations with Frege and Russell, Moore and Waismann, have over-shadowed everything else in his cultural origins and intellectual concerns.