I HA VE tried to make it clear that the scientist approaches the matter .. of .. fact world in a manner not really very different from that of the man in the street. The scientist in his capacity as scientist, however, is prepared to talk only ab out certain things, and to offer as satisfactory only certain kinds of explanation. I have tried to show, too, just how the scientist, and for that matter the layman also, sets about the difficult task of examining the world into which he was born. I have also stressed the fact that the explanatory language of science does not include any reference to private feelings, but only to public matters; and that so .. called public objects were really abstractions of achanging universe-parts chipped out of the world for the purpose of examination.