This book constitutes the first volume of the Proceedings of the 1965 International Colloquium in the Philosophy of Science held at Bedford College, Regent's Park, London, from July 11th to 17th 1965. The Colloquium was organised jointly by the British Society for the Philosophy of Science and the London School of Economics and Political Science, under the auspices of the Division of Logic, Methodology and Philosophy of Science of the International Union of History and Philosophy of Science...