Post-normal science

Post-normal science (PNS) represents a novel approach for the use of science on issues where 'facts uncertain, values in dispute, stakes high and decisions urgent'. PNS was developed in the 1990s by Silvio Funtowicz and Jerome R. Ravetz. It can be considered as a reaction to the styles of analysis based on risk and cost-benefit analysis prevailing at that time, and as an embodiment of concepts of a new 'critical science' developed in previous works by the same authors. In a more recent work PNS is described as 'the stage where we are today, where all the comfortable assumptions about science, its production and its use, are in question'. Post-normal science (PNS) represents a novel approach for the use of science on issues where 'facts uncertain, values in dispute, stakes high and decisions urgent'. PNS was developed in the 1990s by Silvio Funtowicz and Jerome R. Ravetz. It can be considered as a reaction to the styles of analysis based on risk and cost-benefit analysis prevailing at that time, and as an embodiment of concepts of a new 'critical science' developed in previous works by the same authors. In a more recent work PNS is described as 'the stage where we are today, where all the comfortable assumptions about science, its production and its use, are in question'. In 1962, Thomas Kuhn's The Structure of Scientific Revolutions introduced the concept of normal science as part of his theory that scientific knowledge progresses through socially constructed paradigm shifts, where normal science is what most scientists do all the time and what all scientists do most of the time. The process of a paradigm shift is essentially as follows: An illustration of the theory in practice is the Copernican revolution, where Copernicus’ idea of a (sun-centered) solar system was largely ignored (not in the rules) when first introduced; then Galileo was deemed a heretic for supporting the idea (rules called into question); and finally, after a revolution in cosmology, the solar system became an obvious and foundational part of scientific knowledge (new rules). Another example is the question of whether light is a particle or a wave. For a long time there was debate on this point. Advocates on both sides had many valid arguments based on scientific evidence but were lacking a theory that would resolve the conflict. After a revolution in thinking, it was realized that both perspectives could be true. Physicist and policy adviser James J. Kay described post-normal science as a process that recognizes the potential for gaps in knowledge and understanding that cannot be resolved in ways other than revolutionary science. He argued that (between revolutions) one should not necessarily attempt to resolve or dismiss contradictory perspectives of the world, whether they are based on science or not, but instead incorporate multiple viewpoints into the same problem-solving process. From the ecological perspective post-normal science can be situated in the context of 'crisis disciplines' – a term coined by the conservation biologist Michael E. Soulé to indicate approaches addressing fears, emerging in the seventies, that the world was on the verge of ecological collapse. In this respect Michael Egan defines PNS as a 'survival science'. More recently PNS has been defined as a movement of ‘informed critical resistance, reform and the making of futures’. Moving from PNS Ziauddin Sardar developed the concept of Postnormal Times (PNT). Sardar was the editor of FUTURES when it published the article ‘Science for the post-normal age’ presently the most cited paper of the journal. A recent review of academic literature conducted on the Web of Science and encompassing the topics of Futures studies, Foresight, Forecasting and Anticipation Practice identifies the same paper as 'the all-time publication that received the highest number of citations'. 'At birth Post-normal science was conceived as an inclusive set of robust insights more than as an exclusive fully structured theory or field of practice'. Some of the ideas underpinning PNS can already be found in a work published in 1983 and entitled 'Three types of risk assessment: a methodological analysis' This and subsequent works show that PNS concentrates on few aspects of the complex relation between science and policy: the communication of uncertainty, the assessment of quality, and the justification and practice of the extended peer communities. Coming to the PNS diagram (figure above) the horizontal axis represents ‘Systems Uncertainties’ and the vertical one ‘Decision Stakes’. The three quadrants identify Applied Science, Professional Consultancy, and Post-Normal Science. Different standards of quality and styles of analysis are appropriate to different regions in the diagram, i.e. Post-normal science does not claim relevance and cogency on all of science's application but only on those defined by the PNS's mantram with a fourfold challenge: ‘facts uncertain, values in dispute, stakes high and decisions urgent’. For applied research science's own peer quality control system will suffice (or so was assumed at the moment PNS was formulated in the early nineties), while professional consultancy was considered appropriate for these settings which cannot be ‘peer-reviewed’, and where the skills and the tacit knowledge of a practitioner are needed at the forefront, e.g. in a surgery room, or in a house on fire. Here a surgeon or a fireman takes a difficult technical decision based on her or his training and appreciation of the situation (the Greek concept of ‘Metis’). There are important linkages between PNS and complexity science, e.g. system ecology (C. S. Holling) and hierarchy theory (Arthur Koestler). In PNS, complexity is respected through its recognition of a multiplicity of legitimate perspectives on any issue; and reflexivity is realised through the extension of accepted ‘facts’ beyond the supposedly objective productions of traditional research. Also, the new participants in the process are not treated as passive learners at the feet of the experts, being coercively convinced through scientific demonstration. Rather, they will form an ‘extended peer community’, sharing the work of quality assurance of the scientific inputs to the process, and arriving at a resolution of issues through debate and dialogue. The necessity to embrace complexity in a post normal perspective to understand and face zoonoses is argumented by David Waltner-Toews.