For some time now I have been getting tired of the “correlation is not causation” mantra. This slogan is true as far as it goes, but it tends to be used so as to argue that, despite many correlations linking A with B being found in different circumstances, these will somehow never suffice to strongly suggest a causal link between A and B. On the contrary, I argue that correlation is a necessary feature of causation, but not a sufficient proof. I want to change the slogan to: Correlation is not always causation, but it helps find causes.
In doing all this I half-remembered a challenge set by Michael Woodley at the London Conference on Intelligence last April, so after getting the wording from him again, I thought I would bring it to a wider audience:
"Sure, correlation does not equal causation, but find me just one single instance of a causal relationship where there is no correlation (just one would suffice)."
As befits a challenge, I will be offering the traditional bottle of wine to the best instance. Woodley judges, I arbitrate if required, and provide the bottle of wine.