(This is post 4 of 5 on the ‘Limits to prediction’ ACtioN (applied complexity network) meeting organised by the Santa Fe Institute (SFI) and hosted by Willis Towers Watson on 9 September 2016.)
Language, according to Mark Pagel, is one of the things that really distinguishes the human race. No other species on earth has anything close to our diversity of language – there are around 7,000 different languages spoken in the world today.
Pagel’s research helps to explain where this diversity comes from. He borrows techniques from biology and uses them to make inferences about the evolution of languages, with the aim of finding the ancestral roots of several of today’s modern languages.
Focusing on the Indo-European language family, Pagel notes astonishing regularity in the origin and spread of Indo-European languages, similar to the branching processes often drawn to map out the evolution of genes. Previously, there was widespread belief amongst many comparative linguists that words evolved so rapidly that they would quickly run out of any signal of their ancestry. However, Pagel’s work has revealed common ancestry for Indo-European languages as far back as 8,000 to 9,000 years ago.
Borrowing a concept from physics, Pagel analysed the linguistic ‘half-life’ of words i.e. how long one has to wait before there is a 50% chance that a word will be replaced by a new, unrelated form. By determining words that took the longest to change, it is possible to analyse links between language families with the aim of determining the origins of a common language.
Pagel’s research shows that there is a credible inverse relationship between how frequently we use a word and its rate of replacement. Furthermore, about 25 words in the English language account for about 25% of our speech and this trend is seen across a number of other languages. We all use languages in a similar way and Pagel argues that it is therefore reasonable to infer that this is what we have done throughout history. Words must “compete” for relevance and it is through a form of natural selection that some words come to dominate and others to decline in usage. So assuming that the underlying process of language evolution remains the same, these ideas can be used to predict the future.
It is possible to extend Pagel’s research on language to the development of culture and behaviour in the investment industry. Borrowing from Pagel’s link between the persistence of words and their frequency of use, can we identify behaviours amongst investors that have persisted throughout time through common practice, and which negatively or positively influence the industry? By identifying the major influences (for example, adherence to regulatory rules, due consideration of the end saver and wider corporate social responsibility, preservation of profit for shareholders) the Institute can concentrate on those areas of the industry likely to have the greatest impact on shaping behaviour.
Mark Pagel is a Fellow of the Royal Society, Professor of Evolutionary Biology at the University of Reading and External Professor and Science Board member at Santa Fe Institute.
