Two scientists – a neuroscientist and a philosopher – met on the NYU stage to settle a bet on consciousness dating back to Bill Clinton’s presidency. They debated whether science could find a neural mechanism that explains how the brain, a piece of matter, generates subjective states of consciousness such as feelings, thoughts, and emotions.

The controversy began in 1994 at a conference in Tucson, Arizona on the scientific foundations of consciousness. The neuroscientist Christoph Koch and the philosopher David Chalmers have opposing views. Koch argued that consciousness is a scientific problem that can be solved by looking for neural correlates of consciousness – specific patterns of brain activity associated with various aspects of consciousness. Chalmers argued that no physical processes can explain why perceptions are accompanied by conscious sensations. He called this the “hard problem” of consciousness and suggested that the solution might lie in the fact that “information” is a fundamental property of reality.

In 1998, Koch bet Chalmers on a case of wine that within 25 years—that is, by 2023—researchers would discover a “clear” neural pattern underlying consciousness. However, over the following decades, Koch became less sure of his position and acknowledged the complexity of the problem. He also changed his vision of the neural correlates of consciousness and began to see them as dynamic and multilevel processes.

On Friday night, Koch and Chalmers announced the outcome of their dispute. Koch conceded defeat and gave Chalmers a case of red wine from California. He also expressed his respect for Chalmers’ philosophical approach and called for more dialogue between neuroscientists and philosophers. Chalmers thanked Koch for his openness and honesty and stressed the importance of experimental data for a theory of consciousness. He also stated that he did not consider the problem of consciousness to be unsolvable and that he was ready to make a new bet on the future.

Koch then doubled down. He predicted that twenty-five years from now, when he is 91 and Chalmers is 82, consciousness researchers will achieve the “clarity” that now eludes them. Chalmers, shaking hands with Koch, accepted the bet.