But my money’s on the marshmallow test. It’s quite compelling and, apparently, quite famous—Shenk talks about it with great relish in The Genius in All of Us. In the sixties, a Stanford psychologist named Walter Mischel rounded up 653 young children and gave them a choice: They could eat one marshmallow at that very moment, or they could wait for an unspecified period of time and eat two. Most chose two, but in the end, only one third of the sample had the self-discipline to wait the fifteen or so minutes for them. Mischel then had the inspired idea to follow up on his young subjects, checking in with them as they were finishing high school. He discovered that the children who’d waited for that second marshmallow had scored, on average, 210 points higher on the SAT.What immediately struck me after I read this was that the psychologist took the economic concept of time preference, which is the basis of the phenomenon known as the interest rate, and decided to observe it on a micro level in children to see if it correlates with success. Time preference is the idea that we would be willing to forgo consuming something right now, if we could have more of it at some point in the future. Obviously, if offered to have an equal quantity in one or the other time period, we might as well take it now.
Most interesting is how we typically see time preference play out in society: individuals who are more financially successful have a low level of time preference, which means that they are willing to defer consumption to the future. In contrast, less financially successful individuals have a higher time preference, which means that they are more inclined to consume today rather than wait until tomorrow. Keep in mind that financially successful individuals could have achieved their success through any of a number of different paths with any of a number of different character traits or skills, but they generally share in common the characteristic of low time preference. And while correlation does not imply causation, it seems reasonable to consider that at least some ability to look forward is required before an individual becomes successful, rather than becoming forward-looking after success has already been achieved.
While tests administered to children might evaluate various skills, it is not as though future successful individuals necessarily possess all of those evaluated skills or even some of those evaluated skills. It seems more likely, with successful individuals spanning the gamut in just about every way (type of success, method of success, personality, beliefs, etc.), that a better gauge of success is not something concretely tested on an exam like math or writing, but something that could vaguely be described more as the individual's "approach," "outlook," or "way of being" that, when combined with any of those concrete traits (or maybe even none of those concrete traits), will produce a successful individual. Is it therefore possible that this seemingly primitive marshmallow test, based on a theoretical economic precept, is superior to all those exams that evaluate how well a 4 year old puts blocks together because it actually tests for something that successful individuals generally share in common?