Uncertainty

According to the Brundtland report, sustainable development is a development that

“ensures that it meets the needs of the present without compromising the ability of future generations to meet their own needs.” To be able to live up to that, we need to know what the needs of future generations are. Even if we follow the terminology already in practice in this book and use the wider term ‘interests’, this is a task that seems very difficult. There is a large degree of uncertainty regarding the interests of future generations,³⁹⁶ and this problem is also accompanied with some other problems. Anver de-Shalit for instance points out that even if it were possible to foresee the interests of future generations – which he does not believe it is – it would be complicated to compare and weigh their interests against the interests of our contemporaries.³⁹⁷

Another problem is that we do not know for sure what life will be like in the future, how the technology will develop, or even for how long the human species will survive.

Our inability to make reliable forecasts not just about the preferences of future generations, but also about the future in large, makes I.G. Simmons question the entire idea of caring for future generations:

There is time for caution here: if we define justice to include future generations, but cannot forecast the nature of that future at all accurately, then how do we know what to avoid?³⁹⁸

396 Farber 2000 p.s495

397 de-Shalit 1995 p.5, Melin 2001 p.128

398 Simmons 1995 p.71

Simmons does not want to see this as an excuse for a laissez-fair attitude in relation to future generations, but how do we avoid such an attitude? When we look at the problems presented here, one might be tempted to limit our concerns to the present, and possibly to the immediately following generations while leaving the rest to their destiny. Another approach would be to discount our concern for the future at a rate representing the degree of uncertainty. This last approach is used by many economists and some philosophers.³⁹⁹ One fact in favour of discounting rather than a more abrupt cut off-point is that we are dealing with predictions that tend to get more uncertain the further into the future we stretch them.

Discounting would make it possible to lessen our concern successively in proportion to the increasing uncertainty.

Another possibility is put forward by Jan Narveson who suggests that our almost total lack of knowledge of the future can be seen as an argument for confining our concern for the future to approximately the next 50 years.⁴⁰⁰ His argument is that since we are next to totally ignorant, “no rational consideration of the problem is possible …”.⁴⁰¹

One might point out here that if “no rational consideration of the problem is possible”

how can he then conclude that confining our concerns to a special length of time is a better solution than any other solution? I think Narveson is too pessimistic however. In the previous chapter we noted that inertia is not always the best way of handling uncertainty. We found that in situations where for instance important values are at stake, it is more rational to take precautionary measures such as demanding extra high degrees of certainty in order to go through with a project that might threaten the value in question. If we have a situation where our decision may threaten important future interests although we do not know if they will, the conclusion must be the opposite of what Narveson recommends. I.e. in order to be justified to ignore future generations, we should demand a high degree of certainty that future generations will not hold the interest in question. Lack of knowledge should count against ignoring them, not the other way around. The degree of certainty we demand should of course as we saw earlier stand in proportion to how important we suspect the interest to be. This is complicated since that is one of the things we do not know, but which also seems to talk in favour of being extra careful with what we subject them to.

399 See Gower 1995 p.57, Kavka 1996 p.190,202 note8 Kavka also mentions Martin Golding (“Obligations to Future Generations” Monist 56 1972 pp.97-98), Parfit 1987 p.481

400 Narveson 1996 p.40f

401 Narveson 1996 p.41

Parfit is in general negative to discounting and he makes no exception when it comes to uncertainty. He follows the same strategy as before and points out that we have to distinguish between (1) the fact that our predictions get less certain over time, and (2) whether, given the assumption that a prediction is correct, we are entitled to discount the weight of the effect just because it takes place in the distant future. He admits that (1) is often the case, but does not believe that this can answer (2).⁴⁰²

According to Parfit, this is important for two reasons. Both because we should be careful not to “miss-state our moral view”, and because there are situations when predictions do not get less certain over time.⁴⁰³

I agree with the first reason: We should be more cautious about the terminology we use and not claim that we discount on the basis of time as such when we are actually discounting on the basis of diminishing certainty.

How about Parfit’s second reason? Even if he is correct and there actually are such cases, we still have to admit that most prognoses do get less certain over time. On the other hand, it might be that the things we can predict with a higher degree of certainty are important enough to make a difference even if the uncertainty is great in the general case.

Several authors point out cases where our knowledge about future generations is not so bad,⁴⁰⁴ Kavka e.g. points out that we can know about future generations that they will need

“enough food to eat, air to breathe, space to move in, and fuel to run machines”.⁴⁰⁵ This looks correct, but what does it tell us? Even if we agree that they will need fuel for their machines, we don’t know what kind of fuel. When I write this a large amount of alternatives are being developed, and I would not like to put much money on a bet about which of these will be the fuel of the future. Maybe a combination? Maybe something completely different that no one has yet thought of? Our need for things like food, air and water on the other hand is biologically determined and we can assume that these things will not change substantially in the future. All life forms on the planet need water and nutrients, and all “higher” life forms need oxygen. This may not seem like much information to base our concern on, but for this investigation, it is very central. This means that we have to apply our concern for future generations on our previous food discussion, and the same goes for ecosystem services. In order to have a working water cycle, sufficient levels of oxygen, suitable climate

402 Parfit 1987 p.481f

403 Parfit 1987 p.482,486

404 See e.g. Kavka 1996 p.189, Melin 2001 p.129, Munthe 1997

405 Kavka 1996 p.189

etc. we need working ecosystems. This means that the few things we do know about the needs of future generations are still very important for our investigation. It is true that it only takes away some of the uncertainty and therefore only deals with the argument from uncertainty for some particular interests. On the other hand, these interests are very basic and they are directly related to some of the ways where other species are the most important for us.

The conclusion seems to be that we are not justified in using the lack of certainty concerning future generations as an excuse for discounting their interests. We only have some knowledge about a few things but these things are on the other hand very important – and directly relevant for our investigation since they imply that species that have a high instrumental value for us will also have a high instrumental value for future generations of human beings. When it comes to the things we do not know, it seems most reasonable to invoke the precautionary principle. That means that since we do not know whether a particular species will be important for future generations, but have a strong suspicion based on historical evidence that many species will turn out to be important for future generations probably in ways we can not yet imagine,⁴⁰⁶ we should be very restrictive when it comes to doing things that risk leading to extinction, and the burden of proof should lay on the shoulders of those in favour of exploitation.