“When a girl stays in secondary school, she is 6 times less likely to marry young,” UNICEF tweeted on Thursday evening. Education, and especially female education, is one of the pillars of development, with countless positive externalities for society, including, as the UNICEF tweet notes, an older age at marriage. Getting married at an older age may seem inconsequential, but a recent literature has shown that it may partly explain why Western Europe first escaped the Malthusian trap and led to the Industrial Revolution.

During the early-modern period, women in Western European countries began to marry at an older age. While this observation was first made by John Hajnal in 1965, it is only recently that scholars have begun to consider the causes and consequences of this shift. Tine de Moor and Jan Luiten van Zanden in ‘Girl Power‘ argued that because of the preachings of the Catholic Church which promoted marriage based on consensus, the rise of labour markets, and institutions of property rights that encouraged women to work before they marry, Western European women changed the average age at which women married from around 20 to around 25 years. A higher age at marriage meant a shorter period of fertility for women, meaning fewer children were born and a shift thus occurred from having a higher number of children to having fewer children but investing more in them by, for example, sending them to school.

This is a compelling thesis, but the causal direction is not clear. Did women not simply react to the development of labour markets and, if so, what caused such development? Investigating this, Jeanne Cilliers and I considered the Dutch Cape Colony marriage pattern (the paper is only available in Afrikaans). In South Africa, Dutch immigrants (obviously of Western European origin) settled, bringing along their own institutions, like property rights. Yet the Cape did not have a wage labour market similar to Holland, which, we argue, provides a nice experiment to test their theory. We find that the Cape did not exhibit a European marriage pattern throughout the eighteenth and early nineteenth-centuries. It was only after the shift to a wage economy, helped by the discovery of minerals in the interior of the country, that a marriage pattern similar to Europe emerges. This suggests that it is labour markets that causes marriage patterns, and not the other way round.

So here’s some marriage advice from Dr Phourie. Unsure about when to get married? Don’t do it before you’re 25. You may not start an industrial revolution, but, on average, you will have fewer but more educated kids (which is what society needs more of).