Rebound is a metaphor: in order to understand rebound effects in their technical sense in the sustainable development context, it is first necessary to understand the real-world meaning of the metaphor. Indeed, because the metaphor is so readily understandable, it is not realistically possible to make a definition of rebound effects that does not fit within instinctive understandings of the metaphor.

A Rebound is the countervailing effect of an action. This is the metaphor of a bouncing ball, or of the rebounding punch bag. The core content of the metaphor is that there should be  action in one direction; its reversal; and some link of causality between the two. To those with no specific interest in sustainable development this is the entirety of the metaphor’s meaning.

Expanding on the original; simple, and accessible concept of rebound, it has thus become commonplace in work on Sustainable Development to define Rebound effects very widely as any effect which tends to counteract some desirable feature of an action intended to further sustainability [1] , irrespective of any common causality.

The difficulty arising from the use of such a ‘malign’ definition of rebound is, however, not merely that it is  impolitic. When considering the contribution of technological innovation in general, and ISTs in particular, to Sustainable Development, the confusion between Rebound as a narrowly specific effect in defined circumstances, and Rebound as a generic term for adverse effects, becomes so acute as to render the term all but useless. The circumstance arises from two singular characteristics of many (if not all) technological innovations which apply very particularly to ISTs.

The first such characteristic is that the initial socio-economic effects of the introduction of ISTs are very far from being clearly beneficial. It is the secondary effects that produce the benefits and, indeed, the initial action may never have been intended to be benign. This rather cuts across the idea that secondary effects and/or ill effects are definitively Rebounds. The second such characteristic is that the process if introduction of a new technology delivers its benefits in a rather tortuous and often slow fashion which may involve successive waves of benefits and successive waves of dis-benefits (perhaps overlapping) over long periods of time. The whole effect is that our definition and indeed our understanding of Rebounds proves, on examination, to be insufficient and in need of substantial improvement.

Historic Parallels

Among past technological innovations, the creation of railways and of  railway networks seem (particularly because of their networking content) particularly relevant  to the consideration of IST rebounds and offer the benefit of an immense literature, detailed data in enormous quantities, and wide conceptual accessibility to the lay person. Following this particular analogy, then, it may be  valuable to consider what happened when the first railways came.

Transport had existed before the railways: sea transport was cheap and efficient; canals less so; road transport less so again. Much capital had been invested in roads and canals (often with little return) and large numbers of individuals and enterprises derived their livelihood directly or indirectly from them. The construction of a new railway line involved large capital expenditure (and much use of materials and energy); on its completion, transport rates would generally be set below those for road or canal traffic (often quite artificially) so that the previous generation’s capital investment was largely wasted whilst the new generation’s investment duly failed to produce a return. Great social upheaval resulted, with less people employed per unit of transport (but, at least initially, using more material and more energy). If that primary effect (a marginal and artificial cost reduction accompanied by great social and, in due course, economic distress) were the whole story, railways would have shown a great dis-benefit to society and to sustainability. The primary effect here was bad – but that rather misses the point. To quote Mathias ‘The importance of the coming of the railways…. Lies in the fact that they enabled all other sectors of the economy to expand’. The analogy with ISTs here is particularly telling. In the case of the railways, and indeed in many other technological innovations we have a quite simple dichotomy:

Primary effect = bad

Secondary effect = good

It is at the very least possible that this same dichotomy will apply with the technological innovation of ISTs.

In the simpler early arguments of environmental sustainability it was assumed (in accordance with the semantics of the rebound metaphor) first that rebounds were the bad result of a good intention; and second that they were a secondary effect. Where primary = good and secondary = bad then no conflict existed in this understanding of rebounds: but in technological innovation it seems that sometimes (and perhaps always) primary = bad and secondary = good. We must conclude, therefore, that our previous understanding of Rebound will not stretch to meet the requirements of IST’s contribution to sustainable development, and that a more applicable and implementable understanding must be reached. This represents a significant task for TERRA.