In the following pages I have endeavored to show the impact on philosophy of tech­ nology and science; more specifically, I have tried to make up for the neglect by the classical philosophers of the historic role of technology and also to suggest what positive effects on philosophy the ahnost daily advances in the physical sciences might have. Above all, I wanted to remind the ontologist of his debt to the artificer: tech­ nology with its recent gigantic achievements has introduced a new ingredient into the world, and so is sure to influence our knowledge of what there is. This book, then, could as well have been called 'Ethnotechnology: An Explanation of Human Behavior by Means of Material Culture', but the picture is a complex one, and there are many more special problems that need to be prominently featured in the discussion. Human culture never goes forward on all fronts at the same time. In our era it is unquestionably not only technology but also the sciences which are making the most rapid progress. Philosophy has not been very successful at keeping up with them. As a consequence there is an 'enormous gulf between scientists and philosophers today, a gulf which is as large as it has ever been. ' (1) I can see that with science moving so rapidly, its current lessons for philosophy might well be outmoded tomorrow.