We've found the Messiah. Philip was on cloud nine and Nathanael tried to shoot him down. How would you feel if someone told you they had found the Messiah and he was from Ottawa. Ottawa, yeah right. Nathanael was no dummy, every Messianic scholar knew that the Messiah was to be born in Bethlehem.
Facts are facts.
There was a preacher and an astronomer who got into a discussion while they were on an airplane flight. Jesus loves me this I know for the Bible tells me so. Willingness to investigate. Nathanael was initially skeptical but the next thing you see here he's going with Philip to see Jesus. Maybe Philip offered to buy him lunch at Buster's if he'd go.