nuclear energyuse. The culture of consumerism, which prioritizes short-term gain and private interest,
canmake it easy to rubber-stamp authorizations or to conceal information.
185. In any discussion about a proposed venture, a number of questions need to be asked in order to
discern whether or not it will contribute to genuine integral development. What will it accomplish?
Why? Where? When? How? For whom? What are the risks? What are the costs? Who will pay
those costs and how? In this discernment, some questionsmust have higher priority. For example, we
know that water is a scarce and indispensable resource and a fundamental right which conditions the
exercise of other human rights. This indisputable fact overrides anyother assessment of environmental
impact on a region.
186. The Rio Declaration of 1992 states that “where there are threats of serious or irreversible
damage, lack of full scientific certainty shall not be used as a pretext for postponing cost-effective
measures”
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which prevent environmental degradation. This precautionary principlemakes it possible
to protect those who are most vulnerable and whose ability to defend their interests and to assemble
incontrovertible evidence is limited. If objective information suggests that serious and irreversible
damage may result, a project should be halted or modified, even in the absence of indisputable proof.
Here the burden of proof is effectively reversed, since in such cases objective and conclusive
demonstrationswill have to be brought forward to demonstrate that the proposed activitywill not cause
serious harm to the environment or to thosewho inhabit it.
187. This does not mean being opposed to any technological innovations which can bring about an
improvement in the quality of life. But it doesmean that profit cannot be the sole criterion to be taken
into account, and that, when significant new information comes to light, a reassessment should be
made, with the involvement of all interested parties. The outcome may be a decision not to proceed
with agiven project, tomodify it or to consider alternativeproposals.
188. There are certain environmental issueswhere it is not easy to achieve abroad consensus. Here I
would state once more that the Church does not presume to settle scientific questions or to replace
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RioDeclarationon theEnvironment andDevelopment
(14 June1992), Principle15.
