This paper addresses problems related to transferring market concepts to non-market domains. More specifically it is about fallacies following from the use of the commodity concept in environmental valuation studies. First of all, the standard practice tends to misconstrue the ethical aspects related to environmental choices by forcing them into becoming ordinary trade-off problems. Second, the commodity perspective ignores important technical interdependencies within the environment and the relational character of environmental goods. These are all properties that have made many such (...) goods escape the commoditisation pressure of markets in the first place. Further, it is shown that these interdependencies are the source of some of the ethical dilemmas observed. Finally, inherent characteristics of the environment tend to make the concept of the margin, so indispensable to economic calculus, either difficult or irrelevant to define. The commodity 'fiction' twists the perception of the environment from systems preservation to items use or transformation. This is a problem of increased importance as we approach potential systems perturbations. (shrink)