Kuala Lampur, Feb. 27 -- Picture this: a child sits at a table, staring at a single marshmallow. A researcher explains the rules: "You can eat this now, or if you wait 15 minutes, you'll get two marshmallows instead."

The child fidgets, looks away, and even tries to distract themselves, but the temptation is real. Will they give in to the immediate pleasure or hold out for the greater reward?

This, of course, is the famous marshmallow experiment, published in 1970 by Stanford University psychologist Walter Mischel. The study wasn't just about sweets; it was about self-control.

Years later, in separate analyses done in 1989, 1990, 2000, and 2013, researchers found that the children who waited for the second marshmallow tended to have be...