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What Should We Do About Future Generations?

Impossibility of Parfit's Theory X

Published online by Cambridge University Press:  05 December 2008

Yew-Kwang Ng
Monash University, Australia


Parfit's requirements for an ideal Theory X cannot be fully met since the Mere Addition Principle and Non-Antiegalitarianism imply the Repugnant Conclusion: Theory X does not exist. However, since the Repugnant Conclusion is really compelling, the Impersonal Total Principle should be adopted for impartial comparisons concerning future generations. Nevertheless, where our own interests are affected, we may yet choose to be partial, trading off our concern for future (or others') goodness with our self-interests. Theory X' (maximization of number-dampened total utility) meets all Parfit's requirements except the Mere Addition Principle in less compelling cases.

Copyright © Cambridge University Press 1989

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