The Scarecrow is the first friend that Dorothy makes on the yellow brick road, and he's exactly the kind of guy who makes a perfect companion on a road trip. He's up for trying anything because he can't get hurt. And he's loyal—loyal enough to take out his own stuffing to protect in you in a fight (as he does for his pals in "The Search for the Wicked Witch") or abandon his kingdom to help you find your way home (as he does for Dorothy in "Away to the South"). Best of all, he doesn't eat or drink anything (hey, more for us!) or even require sleep because he's…well, a scarecrow.
The thing is, Scarecrow was born yesterday. (Well, technically the day before yesterday. Same diff.) "My life has been so short that I really know nothing whatever," he tells Dorothy. "I was only made day before yesterday. What happened in the world before that time is unknown to me" (4.12). He came into existence when a farmer painted on his eyes, ears, and mouth. Problem is, his first day in the cornfield didn't go so well. A crow made fun of him for not having a brain, and the Scarecrow took it very, very personally.
Worse, now he has a huge complex about it. "I am anxious," he tells Dorothy. "It is such an uncomfortable feeling to know one is a fool" (4.26). And that sense of self-consciousness seems to negatively impact his quality of life. When Dorothy asks him if he thinks a field of flowers is beautiful, he says, "I suppose so. When I have brains I shall probably like them better" (8.42). Will he, though? Because we're about to let you in on a little secret about the Scarecrow: he doesn't need a brain. Wherever he goes in Oz, he's always the smartest guy in the room.
The sad irony of the Scarecrow's life is that his greatest insecurity happens to be his greatest strength. Whenever the gang comes upon an obstacle—and they come upon them all the time—he's the one who thinks their way out of it. When the travelers can't move forward because of a ditch, he thinks to build a bridge. When they're faced with a river, he thinks to build a raft. And when the Lion falls asleep in the poppy field, he engineers a mouse-drawn chariot to haul his big friend to safety. Now, that is ingenuity.
While the Scarecrow doesn't seem to notice his own brilliance, his friends sure do. "That is a first rate idea," says the Lion at one point. "One would almost suspect you had brains in your head, instead of straw" (7.26). The Wizard, too, provides insight into the Scarecrow's situation. "Experience is the only thing that brings knowledge," he says, "and the longer you are on earth the more experience you are sure to get" (15.78). But the Scarecrow's having none of it. "Surely you will think more of me when you hear the splendid thoughts my new brain is going to turn out," he tells Dorothy (16.3). She answers with the obvious: she's always liked him just the way he is.
When the Wizard finally gives him a "brain" (which is just some pins and needles mixed with bran) the Scarecrow gains the confidence he needs to feel good about himself. But the smart thoughts? Those he's had all along. Just like with Dorothy, the Scarecrow's journey as a character is not about change or growth. As he traveled, the Scarecrow didn't gain something new. He just had the opportunity to use intelligence he already possessed—and, of course, to discover that he possessed it.