Roshan Cools discovered that medicines which affect our brains do not always have the same effect: a substance that increases concentration in a person’s brain, can actually reduce the flexibility of that brain. For someone else the effects may be the opposite. Cools is searching for the brain mechanisms behind something that has preoccupied philosophers throughout the ages: human will power. Roshan Cools is a Social Sciences laureate of the Ammodo KNAW Award 2017.