Are 4 year olds smarter than Harvard graduate students?

[mroels]

(Slight psychology content) The two posts about riddles got me thinking about this email I read a while back about a study that was done by Harvard psychology students. Essentially 400 1st graders and 400 Harvard MBA students were presented with the same riddle and given 1 hour to figure it out. Apparently the 1st graders (85% solved it) had no problem figuring it out but the Havard kids did (27% solved). Unfortunatly the email i got was more about the riddle rather than the research...so I ask why were the results what they were?

Here's the riddle:
What is kinder than God, more evil than the Devil, the rich need it, the poor have it, and if you eat it you'll die?

Solve it and post your answer in white, and explain why kids would have an easier time solving this riddle.