deepens the understanding of the science under investigation. By "the latest methods" we refer to the structuralist view which has emerged in the last fifteen years, and which has been success­ fully applied most notably to physical theories. Economics being rather like a stepchild of a reconstructivist philo­ sophy of science, we think much of the interest of this volume to lie just in its attending to the newer enterprise_ We are happy to have brought together at the colloquium some of the few philosophers of scien­ ce working in. this field who share this common goal, and we hope that their essays will stimulate further work. -The contributions to the long-standing enterprise, though perhaps not as urgent, are no less valuable.