What’s the best answer to the Repugnant Conclusion?
Hipólito Morales ∙ 13 min de lectura
The Repugnant Conclusion's foundation is a mixture of ethical theories, logic and mathematical exercises and a gray area bridging them. I’m convinced that an approach based on the critical level values can serve as a good illumination for this obscure connection due to its objective nature, following an alternative path on the similar rhetoric field from the original conclusion. At the beginning, aggregating welfare is perceived as a rough method, that later will be refined in the average, variable values and critical level strategies. At the end of the essay, critical level theories evolve into a more flexible critical threshold that fits better for the human activity.
In order to ease the navigation through welfare domains, “hedon” will be a recurrent term. It represents a happiness point and it’s capped to a maximum of 100, resembling the 100 percent maximum. The scale is limited on purpose to focus on this specific problem, but it can be removed for further discussion on the topic.
The Repugnant Conclusion states that for any possible large population, having each member a superb quality of life, there might be a much larger imaginable population whose existence would be better even though its members have lives that are barely worth living (Parfit, 1984,). It lays on the total utilitarianism approach in which the best outcome is the one with the greatest quantity of whatever makes life worth living, targeting for the maximum utility across the population based on adding all the separate utilities of each individual together. It follows that any loss in the quality of lives in a population can be compensated for by a sufficient gain in the quantity of a population, carrying potential utility, leading to the conclusion. See Figure 1.
The process of adding population is done by mere addition. Having A and being A+ another population with slightly more population but less welfare than A, it seems reasonable to consider A+ somewhat more desirable under the criteria that the addition of lives worth living doesn’t make a population worse. Extending this idea up to Z and Z+ leads us to the Repugnant Conclusion.
Aggregating welfare into a measure of value
Most of the questions about the logical validity of the thesis circle around rejecting total utilitarianism and use another ethical framework in the middle to remediate it and avoid the conclusion.
A possible solution to this problem is to try to quantify the welfare in a population by giving it a number, find a way to aggregate on the top of that number and decide what metrics are intended to be maximized.
The average principle
An explored solution attempt is the average principle, which maximizes the average welfare per life in a population. In this way, a group of 100 people each with 100 hedons is preferred over a group of 1,000 people with 99 hedons each. It can go further; a single person with 100 hedons is better than the welfare of a million people with an average of 99 hedons. It avoids the mere addition problem by blocking the introduction of lives that make the average welfare worse.
However, if we apply the principle strictly, adding a less-than-average life would be considered an immoral act and adding a not-so-bad life to a really bad population would become a moral action.
Also, it can be reduced to encourage the maximum good per person, even if it is only one, justifying hoarding goods that make worth living from others and then kick them off the population. See Figure 2.
It seems reasonable to prioritize the addition of lives based on the value of welfare that each life contributes to. That´s the average: The close it is to the lower asymptote, when the curve of the function starts to flat, the least desirable because it contributes less. The value of this population is equal to the total amount of welfare divided by the number of habitants.
However, if we add tormented lives, with a negative welfare, to an already bad population, the average welfare obtained from that addition can be superior than the average welfare obtained to adding a life worth living to a population with happiness close to the maximum level of welfare, close to the asymptote, resulting in something called the Sadistic Conclusion (Arrhenius, An Impossibility Theorem for Welfarist Axiology, 2000).
Variable value principles
So far, the value of adding worthwhile lives to a population has been constant, is that the case? The value of new people in a decimated population needed for working hands is arguably greater than adding those to a fulfilled group of several millions. It follows that a different approach of consequentialism is applied depending on the population size; when small and welfare-dense, it behaves as total utilitarianism and when large but welfare spread out, as average utilitarianism (Arrhenius, Ryberg,, & T¨annsj¨o, The Repugnant Conclusion, 2017).
This is an improvement from average principle because the first prefers small populations to have denser welfare. Now we are motivated to increase the population.
Next, the function describing the population size becomes an asymptote that contributes with less value the more lives we add to the population until it reaches a point where only completely pleasant lives are welcome, the next better than the previous one. The value of this population is equal to the average wellbeing multiplied by the function applied to population number.
Nonetheless, the approach is still limited by the considerations of the average principle, following a variation of the law of diminishing returns. When the curve starts to flat at the top, it feels undesirable to introduce more people even when they have decent but not superb lives. See Figure 3.
How to compare and measure welfare
From this approach, we can salvage the variable value of people added to a population. It is variable because some groups of people are considered better or worse than the original, meaning we are comparing on against the other. Are we using a fair comparator? Some goods can be incontestable superior than others.
Hence, an improved utilitarian theory should consider the scenarios leading to the undesired conclusions, and very likely include a proper mechanism to evaluate and measure welfare.
Critical level principles
If we have a hedonic scale with a weight of 60 hedons on one side and each life pretending to join a population is first assessed on the other, we find that a person with a life worth 70 hedons positively passes the test, one with 60 is even and one with 40 is negative. This introduces the notion of critical level: a bar set on a certain heigh to allow the addition of population above a level representing a life barely worth living and thus avoiding the repugnant conclusion.
It is a modified version of total utilitarianism where the contribute value of a person’s life is her welfare minus the positive critical level.
This theory has the advantage of allowing large populations because the addition of each life will not be considered for and average. The amount of hedons that someone could bring to the population is always appreciated as long it provides more than the critical level bar. The value of this population is equal to the number of habitants multiplied by the subtraction resulting from the average wellbeing minus the critical level.
One of the major flaws of the previous attempts is the addition of lives not worth living, the existence of a region with negative welfare or a combination of both. This approach is not the exception.
If we imagine a population with a million inhabitants just below the critical level, with an average of -1 hedons, it will be considered worse than another population of a thousand people with an average of -100.
On our minds, it makes more sense to prefer a large population with lives barely below the critical level than a small one living in literal torture. To include them, there should be a tolerance zone which allows people falling in that region to be allowed in the population. It also acts as an umbrella to those who have neutral lives. See figure 4.
This attempt avoids the repugnant conclusion because there is a high enough level blocking the mere addition paradox and also a low enough level to avoid versions of the sadistic conclusion.
Then the welfare’s value fluctuates between the maximum welfare and the lower mark of the threshold. Now we have to determine how to reasonably set the upper and lower limits.
If a person is added above the critical threshold, it is simply good by providing their utilities to the population. When added below the threshold, it would be preferable not to since it can create a bad population. However, people in between these limits have just an acceptable outcome: the closer to the top, the better.
The nuance about this region is that individuals are in a kind of limbo where they have lives worth living or it is better to not exist. This means, for the practicality of the equation calculating the total value of the population, these lives can be treated as second-class good because just barely got included in the group.
Albeit, we prefer to think that anyone’s existence is in itself good and makes the world one way better if their life is worth living. In order to truly legitimize in this idea, the upper and lower bounds for the threshold have to be properly set.
The challenge starts by questioning how to measure the different goods that each individual has, comparing each reading and add them up to weight the value against the scale proposed at the beginning.
For example, supported on deontological theories, the critical threshold individuals or above should have to the value of respecting the basic rights and dignity of all individuals in the population. This apparently innocent claim cannot be easily translated into a number, because it might have a lower value than having free access to all kinds of knowledge according to someone or it can provide a higher amount of welfare than having free medical assistance despite it is something paramount capable of saving thousands of lives.
Another scenario could involve a pre-pandemic population, where the addition of lives resilient to certain diseases or groups of medics that can help to overcome the situation is possible more valuable than adding an ornithologist.
The previous considerations imply the idea that the critical threshold is more than two flat lines, but the intersection of several functions. Each one of them covers a dimension varying from the ethical principles used (e.g., deontological), the values of the individual or society evaluating the population (what is appreciated) or the context of the population being considered (peace or war times). See figure 5.
A very wide and loose threshold area could raise questions about the legitimacy of the accepted individuals and the utility scale as well. If the functions that determine the threshold have a great deviation, it would be more difficult to compare the inputs. If that happens, then it is not dead simple to assert that the population Z is worse than A because the tolerance zone could include some of those barely worth living beings and the repugnant conclusion could not be totally rejected.
In contemplation of previous consideration, some questions to consider at formulating each one of the functions to define the critical threshold are; is there a limit to the happiness or suffering of an individual? It impacts the range of values that a function can take and also how to calculate the total welfare of a population; how the criteria work with positive populations when adding good lives? The most considered case; how it works with positive populations when adding neutral or negative lives? It can become an undesired population; how it works with negative populations when adding good lives? The possibility of turning the tables and convert it into a good one; how it works with negative populations when adding neutral or negative lives? The plausibility of avoiding more repugnant conclusions.
The repugnant conclusion, besides of being part of a checklist of elements to avoid, is also a guide to formulate better questions in the field of population ethics.
It pointed flaws on the classical view of total utilitarianism, and leaded us through the field of average principles, variable value and critical level theories. Sometimes these theories drag us to versions of the sadistic conclusion.
Critical level principles might represent a lighthouse on population ethics because they deal with the paradoxes set by the repugnant conclusion, giving sound arguments to mere addition and undesirable conclusions. The use of formal sciences, real model scenarios, measurable experiments, more predictable outcomes and feedback loops gives the backbone support a theory needs.
However, it is a lighthouse yet to be build; the finding of formal representations of wellbeing is the missing key to unlock a viable ethical theory to satisfy all the principles we might have hoped for.
Even if the critical level threshold theory is not the best answer to the Repugnant Conclusion, it’s not far from the path to the best one, as long as it also includes the mapping from our real world to the abstract one of formal sciences. At the end, population ethics aims to help dealing with real-world decisions which can shape the long-term future of the humanity in a finite world.
Arrhenius, G. (2000). An Impossibility Theorem for Welfarist Axiology.
Arrhenius, G., Ryberg,, J., & T¨annsj¨o, T. (2017). The Repugnant Conclusion. Stanford Encyclopedia of Philosophy, 8-10.
Parfit, D. (1984,). Reasons and Persons. Oxford:: Clarendon Press.