Chile could soon become the first country to incorporate ‘neurorights’ into its constitution to prevent the misuse of artificial intelligence and neurotechnology (see go.nature.com/35qdje5). These rights relate to the way in which mental processes can be monitored and influenced, principally through brain–computer interfaces.

The country’s Senate has launched a project designed to protect five neurorights proposed by Rafael Yuste, a neurobiologist at Columbia University in New York City (see go.nature.com/33trrmc and R. Yuste et al. Nature 551, 159–163; 2017). These include the right to ‘free will’. However, the precise meaning of free will should be carefully debated before it is incorporated as a national or international right.

Free will is a multidimensional concept that poses several unsolved philosophical problems. Most prominent is whether free will is compatible with determinism. Cultural diversity can also influence its interpretation (see N. Chernyak et al. Dev. Psychol. 55, 866–876; 2019). Furthermore, different types of free choice and action have already been included in the Universal Declaration of Human Rights (see articles 16.2, 18 and 21.3; go.nature.com/33t9bhn).

We should therefore work towards developing a consensual, minimal definition of free will. Although such a definition might not close the philosophical debate, it could be ethically operational in that it would help to pre-empt misinterpretations based on legislative loopholes.