This book brings together key players in the current debate on positive and normative science and philosophy and value judgements in economics. Both editors have engaged in these debates throughout their careers from its early foundations; Putnam as a doctorial student of Hans Reichenbach at UCLA and Walsh a junior member of Lord Robbins's department at the London School of Economics, both in the early 1950s. This book collects recent contributions from Martha Nussbaum and Harvey Gram, as well as a new chapter from the editors.