The excessive exploitation and destruction of ecosystems is reducing the biological diversity on our planet day by day. This initiates changes that are both unprecedented and irreversible. The extinction of each species starts a process involving “evolutionary risks”, that is to say: risks that alter the contexts in which they occur and become incalculable in a specific way. Recent Sociology refers to those “evolutionary risks” also as “uncertainty-uncertainties” (Krohn/Krücken 1993: 9): uncertainties the scope and quality of which are themselves uncertain. In my presentation I want to discuss whether Environmental Pragmatism can give a sufficient normative answer to this new type of risks.

In a first section I will point out that a pragmatist epistemology can help us to clarify and broaden the very concept of biodiversity. Influenced by the concept of experience which had been developed by the classical Pragmatists (James, Dewey) Environmental Pragmatists like Bryan G. Norton, Kelly A. Parker, and Ben A. Minteer during the last two decades first of all question the strict distinctions between man and nature on the one hand, and fact and value on the other hand. Starting from their contributions I will plead for a definition of biodiversity which includes structures and processes as well as values, but also covers human beings and their cultures. Moreover I will argue that the concept of biodiversity perfectly fits to the older pragmatist notion of nature as an open, mulitple and indeterminate process. Following Edward O. Wilson, biodiversity is traditionally defined in three stages and encompasses a) the genetic diversity within a single species b) the diversity of species and c), the diversity of ecosystems. In more recent discussions, a fourth stage is frequently added: d) a functional biodiversity representing the diversity of the trophic interactions within a given ecosystem and the functions they are associated with. On a methodological level Pragmatism can help us to understand this fourth stage even better. James' concept of Radical Empiricism for which interrelations, transactions and entangled hierarchies between entities are no less real than those entities themselves, can provide a deep understanding of nature as diversity. If we take into account that biodiversity is nothing but a result and a materialization of evolution, also Dewey's theory of experience as an evolutionary interaction between organism and its environment can help us to understand the relations between process and complexity which is crucial for biodiversity.

In a second section I will focus on possible normative orientations which pragmatism offers us in times of a “Sixth Extinction”. More than other ethical accounts pragmatism can cope with the above mentioned “uncertainty-uncertainties”. As a third way beyond physiocentric and anthropocentric approaches, Environmental Pragmatism supports the argument that natural diversity is worthy of protection on the moral significance of ecological ignorance: It is precisely our ignorance – for example concerning the significance of biodiversity for ecosystem services – that should commit us to responsibility regarding biological diversity.