Through their study of nature Alfred Russel Wallace and Charles Darwin assembled an impressive body of empirical data. In positivist framework, prevailing at their times, they sought to find the explanation for nature’s work through compiling evidence.

But, of course, facts no matter how rich do not make up a theory. They suspected this and worked hard in their quest for a satisfactory model. Wallace and Darwin devised an almost identical theory to explain the work of nature through natural selection. This remarkable coincidence can be, to a large extent, explained by both scholars ‘borrowing’ their explanatory idea from the same source - the theoretical speculation about the dynamics of human population.

This idea was developed some centuries earlier within what was then the incipient ‘science’ of modern humanities, and more specifically economy and politics. In 1588 Giovanni Botero, Italian humanist, produced a book On the Cause of the Greatness of Cities. In this work, first translated into English in 1606, Botero outlined almost an entire thesis on population, better known from Thomas Malthus's famous Essay on the Principle of Population published two centuries later (1798).

Inspired by Niccolò Machiavelli, another prominent thinker of this time, Botero reshaped rationality argument, in fact casting it in moral form as prudence: 'in the decisions made by princes, interest will always override every other argument.'

Machiavelli (1469–1527) and Botero (1540–1617) witnessed growth of capitalism in Italian cities, especially Venice and Genoa; later establishing major successive centres in Antwerp, Amsterdam and London. This early capitalism had global links and consequences but it was firmly grounded in urban centres that dominated the market and flow of capital. So, the city became a practical model and metaphor for society, with strong moralistic and rationalistic perspectives.


Reconstruction of Laetoli fossil footprints
Reconstruction of Laetoli fossil footprints Image: Australian Museum
© Australian Museum

Botero argued that population growth always outpaced the provision of resources. Thus city will eventually be increasingly overpopulated with insufficient supplies of food. This can be rebalanced if a significant number of people dies through starvation, plague, or wars over scarce resources; or if they abstain from marriage and procreation. It was expected, not without reason, that poor people would be decimated by plague and carnage, or they will be forced to sacrifice their urge to procreate being outwitted by people with means and power.

In essence Botero provided a mechanism for survival through competition and selection process.

Darwin explains it best in his own words:

‘In October 1838, … I happened to read for amusement Malthus on Population, and being well prepared to appreciate the struggle for existence which everywhere goes on from long- continued observation of the habits of animals and plants, it at once struck me that under these circumstances favourable variations would tend to be preserved, and unfavourable ones to be destroyed. The results of this would be the formation of a new species. Here, then I had at last got a theory by which to work’.

Alfred Russel Wallace (1823–1913), who independently proposed the same mechanism for evolution, recollected that while he was in bed with a fever at Ternate in the Maluku Islands he thought about Thomas Malthus's idea of positive checks on human population growth and came up with the idea of natural selection.

In its simplified form the theory of evolution imitates the Malthusian theory of society. And, in turn, it justified capitalist model as ‘natural’ with its strong emphasis on brutal competition. Although the theory of evolution was nuanced its most explanatory power lay in its simplicity. Thus the survival of the fittest provided oxygen to social Darwinism, eugenics and various ideologies obsessed with racial purity.

Darwin’s mysterious agency used (in 1839) as an explanation for the demise of Aboriginal Tasmanians is a parallel to Adam Smith’s invisible hand (1759), which aside from its proper interpretation, demonstrates a strong link between explanatory ideas in political economy and natural history.

Explanations:

Capitalism is a social and economic system in which goods, resources and means of production are owned by rich individuals and corporations, not governments or communities. Decisions about production and distribution of goods are made predominantly to maximise profit, eliminate (or outsmart) competitors and to control markets.

The term eugenics is derived from Greek, meaning ‘well born.’ It is an ideology advocating the improvement of the human ‘race’ through the promotion of higher reproduction of people with desired traits (well born), and reduced reproduction of undesired people such as disabled, poor and others defined by race, religion etc.