Natural scientists are being encouraged by environmental and developmental agencies to define and operationalize the concept of sustainability in a “scientific” manner. Such an approach is fraught with dangers because values, opinions, and social influences are an inextricable part of science, especially applied science. Natural scientists’ attempts to define sustainability, particularly to decide what should be sustained, cannot therefore be value‐neutral. They simply end up shifting value judgments to different levels by choosing either a single obvious objective, an arbitrary range of objectives, or an arbitrary method of aggregating different preferences. This lack of self‐reflectiveness on the part of scientists has important consequences for the direction of research and its political implications. Natural scientists should heed lessons from earlier cases of scientists’ involvement in policy and redefine the terms of reference before shouldering their social burden. The dilemma of pursuing objective science in a value‐loaded and socially charged discourse can be resolved by properly understanding the role of analysis and by pursuing a socially grounded pluralistic approach to problem definition and research methodology.