No surprise. Ultimately the test is too simple. Human behaviour too complex. These are a number of reasons why a child might go for the marshmallow or not. And

No surprise. Ultimately the test is too simple. Human behaviour too complex. These are a number of reasons why a child might go for the marshmallow or not. And that could change from day to day, and week to week. It's certainly an interesting idea. But the idea that a single simple test on one day in one hour can effectively predict your future...well, put like that it makes the experiment sound like a visit to a psychic, tarrot card reader, etc. I'm not suggesting it has zero value. Only that you need plenty of additional tests and signals to develop a profile that *might* predict the future.