5. Mono-metrical vs multicriteria evaluation

Sustainability Assessment appears as a formally “impossible” but nonetheless necessary societal activity, whose protagonists may oscillate between domination and generous-spirited, inclusive strategies. With this preparation, we may now return to the theme of measurement and sustainability indicators.  What is the relative place of qualitative and quantitative information, of analytically reconciled measurements and equations versus ad hoc measurements? This leads us to a third dialectical simplification—this time along the methodological plane of SA indicator ambition—by singling out two poles of practice that act as “attractors”:

• Mono-metrical: the desire for a “silver bullet” indicator of “progress towards sustainability”.

• Polyphonic: the admission of multiple organisational forms, scales and multiple “stakeholder” perspectives.

The limits of the mono-metrical position are well rehearsed. In highly complex systems, the forms of uncertainty—including unresolved inconsistencies between reasonable but incomplete analysis methods—may push “deterministic” modelling into a solely “paradoxical” usage, viz., helping to get a feel for the system indeterminacies.

Moreover, setting sustainability goals requires societies to articulate a raft of aspirations, ambitions, obligations and duties—notably the naming of the value forms and the classes of community meriting respect and, more concretely, articulation of the norms for expression of that respect. This can be done through narrative forms that are subsequently translated into working rules and conventions. The Monetisation Frontier here marks the boundary between analytical rigour and narrative clarity, between quantitative measurement and metaphor. The overall landscape of polyphony will comprise stakeholder positionings using a variety of expertises, numerous techniques and many ways of involving deliberative, participatory approaches. But polyphony—narrative or otherwise—also has its distinctive problems. Polyphony tends to degenerate into cacophony, as the very inclusive ideals of SA analysts open the door towards an ad hoc plethora of indicators, with the risk of permanent indecision. The result tends to be, in one respect, a clash of unresponsive monologues and, in other respects, earnest conversations between people who speak different languages or are tone-deaf. The deliberative ideal is paradoxical:

Between these extremes [of monologue and cacophony] we occasionally find a vibrant multivocality in which each voice formulates its view as persuasively as possible, sensitive to the knowledge that others are likely to disagree, and acknowledging a responsibility to listen to what others are saying.

This “vibrant multivocality” corresponds to the ambition for what these authors call “clumsy solutions”.