Given the dire news about climate change/global warming, we often ask why people don't do more to protect the environment. But let's look at it from a different angle: Why would you engage in behaviour to mitigate climate change?


Almost all energy-saving behaviours have two things in common:

  • A certain cost, monetary or otherwise;
  • The fact that a single individual’s contribution is minimal and cannot, in itself, determine the desirable outcome.


Given the cost and the insignificance of the individual's behaviour, it would seem rational to ‘free-ride’, i.e., to not contribute to the generation of this ‘Public Good’ and instead to take advantage of other people’s contributions. However, as the number of free-riders increases, the system breaks down and everyone is in a worse position than had they contributed in the first instance.



In Game Theory this is known as the 'Tragedy of the Commons'. Different ways to avoid the Tragedy of the Commons have previously been discussed, e.g. privatisation of the commons or punishment for free-riders. With regards to climate change, these options are limited: Privatisation only works for certain goods (for instance, air and water cannot be privatised); punishment requires agreement on policies and is difficult to implement on a global scale.



For my PhD research I am thus looking at another possibility, namely how cooperation evolves in the creation of Public Goods. I focus on how behaviours and their traces (i.e., signs of the behaviour that remain in the physical environment) can foster cooperation without direct communication and, crucially, without coercion.

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© Sabine Topf 2017-2019