Thomas Robert Malthus |

Since the end
of the eighteenth century, apocalyptic warnings as regards the unstoppable
increase of the world population have followed one another. In 1798, Thomas
Robert Malthus published

**. This essay includes the famous quotation:***An essay on the principle of population, as it affects the future improvement of society, with remarks on the speculations of Mr. Godwin, M. Condorcet, and other writers*

*Assuming then my postulata as granted, I say, that the power of population is indefinitely greater than the power in the earth to produce subsistence for man.*

*Population, when unchecked, increases in a geometrical ratio. Subsistence increases only in an arithmetical ratio. A slight acquaintance with numbers will shew the immensity of the first power in comparison of the second.*

In 1838, as
a reaction against Malthus and his alarmism, Pierre François Verhoult asserted
in his

**that this growth is not a geometric progression, but follows a***Note on the law of population growth***(see figure). This curve appears frequently in many natural growth processes.***logistic curve*
In spite of
this, the first report of the Club of Rome (

*The limits of growth*, 1974) insisted again on an alarmist position by keeping to the previsions of Malthus (an exponential growth) without taking into account the study by Verhoult. In this context, several political and social movements have presented contraceptives and abortion as inevitable measures to save humanity from the disaster of overpopulation.
However,
current forecasts are very different. In 2012 the UN published its data about
the growth of the world population from 1950-2010, which showed that the growth
rate has declined, and that the turning point of the curve (which is looking
more and more like the logistic curve) was gone through around 1985. Based on
these data, the UN have made several estimates of the future growth of the
world population, the most optimistic of which predicts that a maximum of some 8300
million people will be reached by 2050.

Based on
these data, and other less detailed covering the period between 1900 and 1950,
the authors of this post have approximated the real growth of the world
population and its extrapolation till 2050 by the following mathematical
expression:

The figure
at the left compares the U.N. data (real and predicted, in red) with those
generated by the previous equation (in blue). Next we have estimated the
development of the world population if anti-natalist policies had not been implemented
around the seventies. We have obtained the following results: the turning point
would have been delayed until 1990, just five years later. And by 2075 the
population would have reached a maximum of 9 billion: 700 million more people, about
twenty five years later.

The
inevitable conclusion is that anti-natalist policies do not give the expected
results. This is now so obvious in China, that it has led them to put an end to
their one-child policy. The hundreds of millions of children sacrificed on the
altar to Moloch have not been killed to save humanity, but so that we can share
a little more for a little longer. It won’t be surprising if posterity accuses
us of barbarism for allowing abortion against
all scientific evidence, just as we accuse our ancestors for allowing
slavery.

**Manuel Alfonseca**

**Julio A. Gonzalo**

Thank you for this post. I had not heard of Verhoult or his study before. The population alarmists are forever talking about the exponential growth of population -- your development of the logistic model is very helpful and clear.

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