Introduction

This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book describes four accounts of constructivism in order to introduce and discuss the following forms of constructivism: Kantian, Humean, Hegelian, and theistic forms. Some constructivists suggest that the evolution of mathematical ideas, whereby only those ideas that are able to solve new problems are selected, can explain the relative success of mathematics. Constructivists hold to a kind of antirealism in the metaphysical sense, denying that moral facts can exist independently of the attitudes of the relevant respondent(s). Meanwhile, the constructivist holds that realism so understood is not a necessary condition for moral objectivity. Kantian constructivism has established itself in contemporary philosophy as one of the most important metaethical alternatives to moral realism and skepticism about the existence and nature of normative truths.