Walter Mischel, the psychologist behind the famous marshmallow test, has struggled with the very issue he studied. Maria Konnikova writes:
“Mischel has travelled around the world to study delayed gratification in various cultural and socioeconomic contexts. The principles from the marshmallow test seemed to hold universally. But, even as he was learning just how important self-control is to success in life, he couldn’t keep himself from smoking.”
Photograph by Adrian Nakic / Getty.