A classical viewpoint claims that reality consists of both things and stuff, and that we need a way to discuss these aspects of reality. This is achieved by using +count terms to talk about things while using +mass terms to talk about stuff. Bringing together contributions from internationally-renowned experts across interrelated disciplines, this book explores the relationship between mass and count nouns in a number of syntactic environments, and across a range of languages. It both explains how languages differ in their methods for describing these two fundamental categories of reality, and shows the many ways that modern linguistics looks to describe them. It also explores how the notions of count and mass apply to ''abstract nouns'', adding a new dimension to the countability discussion. With its pioneering approach to the fundamental questions surrounding mass-count distinction, this book will be essential reading for researchers in formal semantics and linguistic typology.