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Population Wars: Adam Martin replies to Global Population Speak Out

by Adam Martin

I appreciate the thoughtful GPSO reply to my blog post. But I respectfully decline the offer to sign their pledge. Here is why:

Projections of population into the future that fail to account for the power of changing incentives are intellectually sterile explanations and policies that deny the rational response of individuals to incentives will prove impotent or worse.

Why are market-oriented economists so confident that population will be self-regulating? Well, under a regime of property rights, as we use up any scarce global resources, they will become relatively more scarce. This will put upward pressure on their prices. The first response is for individuals to cut back their consumption, but that’s not the most important adjustment (that’s only short term, after all).

The more important response is the one Julian Simon pointed out: the increase in resource prices creates an incentive to find more efficient means to use them or to come up with substitutes. Innovation of what we use and how we use it is the best path we know of to sustainability in development. Institutions such as property rights, the family, and, yes, even money are preconditions for aligning incentives with conservation and unleashing systematic resource-saving innovations.

Here both our deepest moral commitments, as well as sound economics, overlap with the professed beliefs of GPSO: certainly women should not have reproductive decisions forced upon them. So the message is not that nothing can go wrong. Absent secure individual rights, individual responsibility, and free markets, quite a bit can: first and foremost for the victims of injustice. However, simply admitting that these problems are real is a long way from endorsing statements like this (from the email I was sent):

the current size and growth of human population [is] a sustainability issue no less crucial than over-consumption in developed nations and all the resultant emissions, habitat loss and toxic pollutants. [emphasis in original]

I want to raise two problems with these sorts of statements. First, admitting that population growth can have adverse consequences is a long way from admitting that anyone has the knowledge to determine the “right” population size, even roughly. Statements like the one above, not to mention the affiliations of some of GPSO’s signees–convince me that they believe otherwise. And I’m not arguing that sustainable population size is a difficult calculation to make, I’m arguing that it’s meaningless. Sustainability means a balance between what present and future individuals want to do and can do. When human capacities and desires are by their nature heterogenous and changing over time–as in the long run that sustainabilitistas worry about–then what counts as sustainable is simply not knowable unless one knows current and future capacities and desires.

Second, I want to raise the question as to whether a “public discussion addressing the size and growth of human population” is compatible with those individual rights. If governments decide what the right population size is, and the actions of free and responsible individuals give rise to a different population size, either the population target or individual rights must be sacrificed. I believe–I hope–that the GPSO signees would abandon their plan. History has shown too many willing to do the opposite. It is for this reason that, while I obviously do not believe women should be coerced, I cannot sign onto “population justice” as defined by GPSO.

If it is excessive procreation we are worried about, we would do well to remember the words of Henry Simon: “Academic economics is primarily useful, both to the student and to the political leader, as a prophylactic against popular fallacies.”

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  1. E Aboyeji wrote:

    The dissapointing and ironic fact is that too often while such discussions about who should reproduce and why pretend to be pro poor and empowering of women, when we get down to reality, the opposite is the case.
    I am sure this organisations version of population justice does not account for the India and China’s missing girls, or the many special needs children or the many black and latin Americans that are not “good” for the “sustainability” of our planet.

    Eugencists…fear them!

    Posted December 13, 2009 at 4:27 pm | Permalink
  2. KS wrote:

    If I’ve followed your argument correctly Adam, you believe, along with other confident market-oriented economists, that the world population will be self-regulating… one day… in the future… when everywhere in the world we have the ‘proper’ institutions, individual rights, individual responsibility, and free markets and thus everyone will behave rationally in response to the correct incentives.

    And do you believe that this will happen all in time and well before any disasters arise from population pressure?

    The very name OPT does suggest that there might be a specific optimum population, for a specific sustainability, and this is clearly very problematic. But in fact the idea of sustainability does in fact imply that with changing futures, changing technologies, any specific total population might be variable. The argument being made is that presently the impact on the planet of the total population is too negative and will not be self-regulated in an acceptable time. Would the title ‘optimum population growth rate’ be more palatable to you?

    I’d argue that your argument that acceptable self-regulation will occur has already likely to be proved false. If climate change processes have actually passed a threshold, triggering irreversible change, then I’d argue you’ve been proven wrong already and we’ll find out quite soon.

    Furthermore, it seems to me that it’s been proven at national levels repeatedly that such self-regulation simply is not occurring and does not ever occur in time to avoid catastrophe. But what a catastrophe means is of course a morally subjective question. As indeed are ‘acceptable’, ‘optimum’, and ‘sustainable’.

    My observation is that population pressure can be demonstrated as a cause of conflict, death, and suffering, in addition terrible impact on the ecology, which for me are a moral imperative to try and prevent – before the utopian dream of perfect institutions and perfect markets.

    In common with other economists your arguments seem a bit confused about moral philosophy. You’d really like to avoid it and make nothing but economic arguments as if they aren’t inherently based on a very subjective set of morals. You’re unwilling to consider the moral question of individual reproductive rights vs. common (human) interest or the ecology of the planet. Yet, your real objections seem to really be based on morals – an underlying fear of immoral population control and a moral belief that reproduction is sacred. But what does that mean? In this case, it seems to mean that you feel this particular individual right is more important than collective interest (defined by government policy) but you say it as if sacrificing the rights of individuals isn’t fundamental to the very idea of government and states.

    I really find it hard to believe that the Optimum Population Trust has a secret agenda but what exactly are you trying to suggest with “not to mention the affiliations of some of GPSO’s signees”? I’m perhaps naive.
    Discussing reproduction policies (such as promoting reproductive rights, women’s rights generally, promotion of family planning and fighting the Roman Catholic church) should not be dismissed and ignored due to a fear of past moral travesties. They should be discussed with a clear view of those past horrors.

    Your puns are very good. But I think unfairly directed. Discussions of population do not all fail to account for future incentives and responses.

    Posted December 14, 2009 at 3:27 pm | Permalink

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  1. By uberVU - social comments on December 12, 2009 at 7:47 pm

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    This post was mentioned on Twitter by bill_easterly: Aid Watch Population Wars Continue: Adam replies to Global Population Speak Out

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