The quest of the International Brain Lab (IBL) to determine the role of the brain in foraging behaviour (Nature 549, 319–320; 2017) follows centuries of testing the outcome of different brain manipulations. Those experiments failed to link correlations with causality (see P. Södersten et al. Med. Hypotheses 77, 371–373; 2011).

The brain might instead act as a mediator between controlling factors in the environment and behavioural output. Perhaps, like evolution, it functions as a tinkerer, equipped with a range of signalling or other mechanisms that allow adaptation (see F. Jacob Science 196, 1161–1166; 1977).

Life would be more enjoyable if so, because the IBL's proposed model of a brain that integrates information and makes moment-to-moment decisions would otherwise leave us with nothing to do.