The main question addressed in this book is whether individuation of the contents of thoughts and linguistic expressions is inherently holistic. The authors consider arguments that are alleged to show that the meaning of a scientific hypothesis depends on the entire theory that entails it, or that the content of a concept depends on the entire belief system of which it is part. If these arguments are sound then it would follow that the meanings of words, sentences, hypotheses, predictions, discourses, dialogs, texts, thoughts and the like are merely derivative. The implications of holism about meaning for other philosophical issues (intentional explanation, translation, Realism, skepticism, etc.) will also be explored. Authors discussed include Quine, Davidson, Lewis, Bennett, Block, Field, Churchland, and others. The book is intended for all those interested in language, mind, metaphysics or epistemology.