One year older and all the more wise, child genius Arden Hayes went back to chat with Jimmy Kimmel for a third time and schooled him on the Periodic Table of Elements.
The Tonight Show host quizzed Arden by asking him to guess a few elements' atomic numbers and symbols -- which he passed with flying colors. Then the whiz kid named all 118 of them, in order.
Arden, who also has an extensive knowledge on U.S. presidents and geography, got to meet with former President Bill Clinton before the show as well. But when Kimmel asked him if he wants to be a president one day, Arden said he isn't so sure.
"Mmm, I still want to be a chemist," he says.
No hard feelings, Bill.
(Correction: A previous version of the article mistakenly identified 188 elements on the periodic table instead of 118. A correction has been made to reflect the correct number.)