Guest Post by Ravi Saraogi
What if I told you that poor hygiene in Western countries was an important reason for them being wealthier than Asian countries during the medieval era (circa 1400 – 1800). Sounds quirky right? But this is indeed true.
Medieval Europe: Human excreta was collected in pots and thrown into the street Source: http://www.haciendapub.com/medicalsentinel/medical-history-hygiene-and-sanitation
Really? How is this possible?
Prior to the Industrial Revolution (circa 1800-1850), civilization was subject to the Malthusian Trap. This trap worked in two ways. Every time efficiency growth outstripped the growth in population, birth rate would increase. This would lead to per capita income remaining constant as the extra income generated out of growth in efficiency had more mouths to feed. Similarly, every time efficiency growth lagged the growth in population, population would fall. This is because the fall in efficiency growth would lead the income to be insufficient to support the growth in population. Again, per capital income would remain constant in this case too as the income fall was accompanied by a fall in population.
So, under the Malthusian Trap, there are three ways in which per capital income can be increased,
- Higher growth in efficiency
- Lower birth rate
- Higher death rate
Before the Industrial Revolution, growth in efficiency was very slow, so option (1) is out. That leaves us with lower birth rate or higher death rate. With this background, we can answer the question – why was there a positive link between poor hygiene and higher incomes prior to the Industrial Revolution? Simple, poor hygiene lead to higher death rates.
But how do we know hygiene in Western countries was poorer than Asian countries?
Gregory Clark, in his book ‘A Farewell to Alms’ devotes a nice section on this. For instance, he mentions that,
“Another factor favoring high living standards for Europeans compared to Asians is that throughout the preindustrial era Europeans were—by modern standards and also those of preindustrial China and Japan—a filthy people, living in dirt and squalor. The low standards of personal and community hygiene are everywhere apparent in preindustrial Europe. Indeed the travel diaries of European visitors to Japan in the years 1543–1811 frequently stressed the extreme cleanliness of the country by contemporary European standards.” 
Particularly interesting is Clark quoting in his book an extract from a certain Samuel Pepys’ diary in October 1660, “Going down to my cellar . . . I put my feet into a great heap of turds (lumps of excrement), by which I find that Mr. Turner’s house of office is full and comes into my cellar.”  It appears that overflowing faeces matter from your neighbour’s house was not a big deal in medieval England!
Medieval Europe: People used to pee and poo in pots kept under their beds. Source: http://www.littlethings.com/shocking-hygiene-practices/?vpage=1
Furthermore, “In contrast in China and Japan human waste, urine as well as feces, was a valuable property which householders sold to farmers, and which various groups competed for the right to collect. Waste was not dumped into cesspits, sewers, and streams, contaminating water supplies. Instead in cities such as eighteenth-century Osaka contractors found it profitable even to provide public containers on street corners in order to profit from the waste deposits.” 
People changed clothes only occasionally: King James VI of Scotland went months at a time without changing his clothes. Source: http://www.littlethings.com/shocking-hygiene-practices/?vpage=2
This is apart from other poor hygiene habits in medieval Europe like rarely taking baths and only occasionally changing clothes. Asians were apparently way more hygienic. “… in Japan bathing in hot water was popular and frequent. The Chinese also bathed whenever possible, and they employed plenty of soap. The Japanese washed their hands after urinating or defecating, and they kept privies clean.”
Showers and tubs were rarely found in the home. When people did bathe, it was usually in a common area where hundreds of others had bathed. Source: http://www.littlethings.com/shocking-hygiene-practices/?vpage=2
Unfortunately, the rules of the Malthusian Trap was such that better hygiene and sanitation led to a lower death rate in Asian countries and they were “punished” as meagre incomes had to support larger populations.
So, should we infer that to become wealthy, countries should neglect sanitation and hygiene? Absolutely not. Luckily, the positive relationship between poor hygiene and per capita income during the Malthusian era broke down during the Industrial Revolution.
Industrial Revolution and the Escape from the Malthusian Trap
Something happened in England during the Industrial Revolution (circa 1800-1850). The rate of growth in efficiency multiplied by leaps and bounds. No longer was birth and date rates an important determinant of per capita income. Take a look at the graph below:
Source: Hoppe, Hans-Hermann, 2013, From the Malthusian Trap to the Industrial Revolution, Mises Circle Feature
For most of human history, per capita income was broadly constant. As highlighted earlier, this was because any gain in efficiency which resulted in additional income was just about enough to feed the growth in population, so that income per head remained more or less constant. But around 1800, things changed in Western countries when the growth in efficiency far outstripped the growth in population, leading to a sharp increase in per capita income.
Which is to say that post 1800s, efficiency became the central determinant of per capita income. No longer do birth and death rates play any significant role in influencing per capital income. With this, the “advantage” that unhygienic countries had over hygienic countries is gone. All countries now have the right incentives to push for better hygiene and sanitation facilities.
Aren’t we glad?