This book is a comprehensive introduction to the philosophical foundations and development of modern biological classification.

Richard A. Richards is Professor of Philosophy at the University of Alabama. His publications include The Species Problem (Cambridge, 2010) and many journal articles.

1. Why classify?; 2. The Aristotelian framework; 3. The Darwinian pivot; 4. Evolutionary taxonomy and the Cladistic challenge; 5. The tree of life; 6. The species problem; 7. The metaphysics of biological classification; 8. Theory and the world; 9. The essential tension.