Warren Weaver's essays and reflections span his remarkable career as a mathematician, science administrator, and public intellectual who helped shape American science in the twentieth century. Weaver directed the Rockefeller Foundation's program in natural sciences, where he coined the term molecular biology and funded the research that would transform life sciences. His work on communication theory with Claude Shannon laid foundations for information science. The book collects Weaver's writings on science and society, examining how scientific institutions should be organized, how research funding should be allocated, and what obligations scientists bear to the public. Weaver writes accessibly about complex subjects, drawing on his experience at the intersection of science, policy, and philanthropy. He reflects on the changes he witnessed in American science, from the relatively small-scale enterprise of his youth to the massive research establishment that emerged after World War II. The essays address perennial questions about the relationship between basic and applied research, the role of private foundations in supporting science, and how scientific progress can be communicated to general audiences. Weaver's perspective, that of someone who helped build modern scientific institutions, provides valuable insight into their purposes and limitations.