This book is about the ways that philosophers inquire into science. They do so with several different approaches, which this book parses into three. One analyzes the results of inquiry, another the process of inquiry, and still another inquiring, or what it means to be an inquirer. Each approach puts a different feature of science centre-stage - its logic, practice, and being-inquiring - questions it in different vocabularies for different ends, and ends up with different kinds of conclusions. This book outlines these approaches in a non-technical way, and highlights their differences by showing how they engage specific topics and issues in physics, including method, discovery, and theory. The key audiences for this book include the wider physics community, as well as philosophy and physics students.