It seems that once upon a time (probably in the 1980's) a group of reseachers got together and speculated on the human ability to sacrifice pleasure in the present for greater pleasure in the future. For example: using human-edible bait to lure greater prey, opening savings accounts, etc. The question was: Is this ability in-born, or is it learned?

To answer the question, they conducted a series of experiements. One of these was presenting a small child with the following dilemma:

Here is a marshmallow. You can take it and eat it. But, if you don't eat it, I'll give you another marshmallow in a while.

The results of the tests were inconclusive. But either way, that one test gave rise to the concept of a 2-marshmallow person and (of course) the 1-marshmallow person. The first being a person who was willing to wait for greater gains, while the latter was a person seeking quick satifaction, regardless of possible future loss.