On the Buddhist Truths and the Paradoxes in

  Population Ethics




     B.Contestabile    admin@socrethics.com                                                           First version 2007   Last version 2014








Starting point

Starting point of this paper is the following citation concerning the state of contemporary population ethics:

“Most discussion in population ethics has concentrated on how to evaluate populations in regard to their goodness, that is, how to order populations by the relations “is better than” and “is as good as”. This field has been riddled with paradoxes which purport to show that our considered beliefs are inconsistent in cases where the number of people and their welfare varies.” [Arrhenius 2004, 201].



Type of problem

The best known and most discussed example shattering our intuitions is Parfit’s

Mere Addition Paradox. This paper explores the potential of the Buddhist Truths to answer the following questions:

         What is at the source of the Mere Addition Paradox?

         Why are paradoxes unavoidable in population ethics?




         The comparison of classical utilitarian and Buddhist intuitions demonstrates the close tie between intuitions and interests. The perplexing Buddhist intuition about non-existence can be explained (except for metaphysical reasons) by a radically different priority given to survival.

         The method of measuring the quality of life is not decisive for the existence of paradoxes. The Buddhist axiology changes but doesn’t remove counter-intuitive combinations.

         If the conflict of interest (quantity versus quality) is described within a two parameter model, it causes conflicting intuitions. In axiologies which favour quantity (utilitarianism) or quality (perfectionism) the conflicting intuitions inevitably lead to paradoxes.

         In order to find a compromise one would have to find a universal interest and a corresponding universal intuition. The obvious candidate to meet this request is sympathy. But since there is no universal consensus on the desirable degree of sympathy, the normative force of such an approach is limited.

         Breaking out of the two parameter model and accepting the incommensurability of certain qualities threatens the normative claim of population ethics.










The full text was published 2010 in


Contemporary Buddhism, Volume 11, Issue 1













How many people should there be?          

The answer depends on the following assumptions:

1)      The assumption that there are incommensurable levels of welfare. In this case there is no normative answer.

2)      The assumption that all levels of welfare are commensurable. In this case a normative answer can theoretically be given.

a)      The assumption that total welfare is positive (which triggers an expansive policy)

b)     The assumption that total welfare is negative (which triggers a contractive policy)

3)      The assumption that non-existence is a perfect state. In this case the answer is trivial and does not depend on commensurability.




The Speed Limit example [Contestabile, 110-111] is useful to introduce the concept of incommensurability, because it compares the convenience of the car drivers with the suffering of traffic victims.

According to Arrhenius the only way to avoid paradoxes is by questioning commensurability and breaking out of the two-parameter model [Contestabile, 112].


The aggregation of incommensurable preferences is the most general approach to solve conflicts of interest (like quantity versus quality). The “repugnancy” of a population [Contestabile, 105] can be considered to be a matter of individual preference. A majority-definition of “repugnancy” is then derived by aggregating the individual preferences for each combination of population-size and welfare. If the individuals are well informed about the consequences of a certain population policy and if they can freely express their attitude towards risk, the aggregation of their preferences delivers an inter-subjective criterion to decide between policies. The focus shifts to forecasting and educational advertising.


         There is a theoretical hurdle in the process of aggregation. Incommensurable preferences lead to Arrovian impossibility theorems [Arrhenius 2000, 15]. No voting system can convert the ranked preferences of individuals into a community-wide ranking while also meeting a certain set of reasonable criteria [Arrow]. In practice this theoretical obstacle can be bypassed. The arrovian impossibility theorem only becomes effective if three or more options are at stake – not if the voters have to confirm or decline a specific policy.

         A more disturbing problem is the protection of minorities. Under certain circumstances the aggregation of preferences allows exterminating a minority by majority decision [Hare, 121-122]. Theories of justice [Rawls] prevent the worst cases of abuse, but in less evident cases (like the Speed Limit example) the problem reappears. The majority decides what kinds of suffering are tolerable.



Positive total welfare

According to the first Noble Truth there is an unresolvable conflict between the classical utilitarian interest to expand life and the Buddhist interest to avoid suffering. The interest to expand life stands for the quantity (size) of the population: the interest to avoid suffering stands for the quality of life [Contestabile, 109].


Classical utilitarianism doesn’t have a preference for quantity. The total can be augmented by an improvement of quality as well.

But the fact that the improvement of quality takes more energy than the multiplication of the same quality favours expansion at the cost of quality.


         It is easier to copy an invention than to invest in research (e.g. generic drugs)

         It is easier to procreate than to improve the quality of life [Parfit, 387-390].

In cases where the population size is no issue – like the Speed Limit example [Contestabile, 110-111] – it is more efficient to improve the welfare of the happy majority than the one of the suffering minority. A small improvement of the majority’s quality of life has the same effect as a big improvement of the minority’s quality.


Expansive population policies at the cost of quality can be prevented by comparing averages:

The most popular theory among welfare economists, Average Utilitarianism, ranks populations according to the average welfare per life in the population [Arrhenius 2000, 53].

As any other axiology the devaluation of the population size has its theoretical deficiencies [Arrhenius 2000, 53-57], but they do not make the method impractical:

         The theory says that a tiny population is better than a large population, if the former has a minimally higher average life satisfaction. In practice, however, the average quality of life decreases (at some point) in a shrinking population, so that smaller populations become unattractive.

         The improvement of the average at the cost of a suffering minority can be prevented by assigning more weight to the suffering people in calculating the average.


Since average utilitarianism concentrates on quality, the question “How many people should there be?” can now be answered as follows:

The best population size is the one that produces the highest average quality of life”.

This theoretical answer is still far from a concrete value, because

         there are many other factors influencing the quality of life, so that it is difficult to determine the influence of the population size

         resources can (in some cases) be increased by technological innovation.

Thesis: There is an optimal range of population sizes, below and above which the (weighted) average quality of life decreases. The optimum depends on the historical situation.



Negative total welfare

Insofar as the Speed Limit example [Contestabile, 110-111] is concerned with the distribution of welfare among a fixed number of people; it does not contribute to population ethics [Arrhenius, 110]. Its relevance concerns the comparison with an empty population.

         If the suffering of the traffic victims surpasses the happiness of the drivers, then – according to classical utilitarianism – it is better to stop mobile traffic.

         If the suffering within a population surpasses its happiness, then – according to the same logic – it is better to stop procreation; non-existence is the lesser evil.

But the empty population is only a theoretical option. In practice it is impossible to eradicate humanity by global voluntary childlessness or by a conscious violent self-destruction. Populations with negative total welfare have to be analysed like the mirror image of populations with positive total welfare [Broome, 213].

         For the rationality of a negative total, see The Denial of the World from an Impartial View.

         The answer to the question “How many people should there be?” is the same as above, but the task is to minimize a negative average, instead of maximizing a positive average, see Hostility and the Minimization of Suffering.



Non-existence as a perfect state

A completely different vision – represented by some forms of Buddhism – says that non-existence is a perfect state [Contestabile, 108].

In this case the answer to the question “How many people should there be?” is an unconditional “None”.

For more information about this intuition, see Negative Utilitarianism and Buddhist Intuition.



Axiology and interest

The axiology decides about the definition of a life worth living. The same population can be assigned a positive or negative total welfare depending on the axiology which is chosen:

1.      If the axiology does not allow negative values, then every life is worth living and total welfare is always positive.

2.      If the axiology does not allow positive values, then no life is worth living and total welfare is always negative.

The choice of the axiology is driven by interests:

§  The biological interest to expand life tends to choose an axiology where total welfare is positive.

§  The Buddhist interest to avoid suffering tends to choose an axiology where total welfare is negative.

The predominating assumption that total welfare is positive, might be the result of a distorted perception, caused by the biological interest to expand life,

see Negative Utilitarianism and Buddhist Intuition.










1.      Arrhenius Gustav (2000), Future Generations, A Challenge for Moral Theory, FD-Diss., Uppsala University, Dept. of Philosopy, Uppsala: University Printers

2.      Arrhenius Gustav (2004), The Paradoxes of Future Generations and Normative Theory, in the Repugnant Conclusion, Essays on Population Ethics, 45-60, Dordrecht, Holland: Kluwer Academic Publications

3.      Arrow Kenneth J. (1966), Social Choice and Individual Values, Wiley, New York

4.      Broome John (2004), Weighing Lives, Oxford University Press, New York

5.      Contestabile Bruno (2010), On the Buddhist Truths and the Paradoxes in Population Ethics, Contemporary Buddhism Vol.11, No.1., Routledge, London

6.      Hare Richard Mervyn (1976), Ethical Theory and Utilitarianism, Contemporary British Philosophy, H.D. Lewis Ed.

7.      Parfit Derek (1984), Reasons and Persons, Clarendon Press, Oxford

8.      Rawls John (1971), A Theory of Justice, Belknap Publishers, Cambridge

9.      Socrethics, Philosophy as Therapy