This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book explores a number of interrelated themes that have been central in pragmatism scholarship since the earliest stages of the development of the pragmatist tradition: truth, objectivity, rationality, value, and the controversy between realism and idealism. It examines that how Rescherian realism, idealism, pragmatism, and pluralism hang together as a complex set of philosophical commitments. The book takes up fundamental issues in pragmatist philosophy of science, including scientific inference, scientific explanation, and scientific realism, identifying Charles S. Peirce as the pioneer figure to whose views Rescherian objective pragmatism is to a considerable extent indebted. It discusses pragmatic realism as a philosophy of inquiry as well as the Peircean dimensions of objective pragmatism. The book also introduces the notion of homo quarens and seeks to account for the specifically pragmatist conception of inquiry, emphasizing its Peircean but also Deweyan background.