His name is Jay Greenberg, although he likes the nickname "Bluejay" because, he says, blue jays are small and make a lot of noise.
Greenberg says music just fills his head and he has to write it down to get it out. What's going on in Bluejay's head? Correspondent Scott Pelley spoke with him.
Jay wrote a piece, "The Storm," in just a few hours. It was commissioned by the New Haven Symphony in Connecticut.
When the last note sailed into the night, Jay navigated an unfamiliar stage, and then took a bow.
"We are talking about a prodigy of the level of the greatest prodigies in history when it comes to composition," says Sam Zyman, a composer. "I am talking about the likes of Mozart, and Mendelssohn, and Saint-Sans."
Zyman teaches music theory to Jay at the Juilliard School in New York City, where he's been teaching for 18 years.
"This is an absolute fact. This is objective. This is not a subjective opinion," says Zyman. "Jay could be sitting here, and he could be composing right now. He could finish a piano sonata before our eyes in probably 25 minutes. And it would be a great piece."
How is it possible? Jay told Pelley he doesn't know where the music comes from, but it comes fully written -- playing like an orchestra in his head.
"It's as if the unconscious mind is giving orders at the speed of light," says Jay. "You know, I mean, so I just hear it as if it were a smooth performance of a work that is already written, when it isn't."
All the kids are downloading music these days. But Jay, with his composing program, is downloading it from his head.
The program records his notes and plays them back –- that's when the computer is up and running. Jay composes so rapidly that he often crashes his computer.
"It's as if he's looking at a picture of the score, and he's just taking it from the picture, basically," says Zyman.
Jay's parents are as surprised as anyone. Neither is a professional musician. His father, Robert, is a linguist, and a scholar in Slavic language who lost his sight at 36 to retinitis pigmentosa. His mother, Orna, is an Israeli-born painter.
"I think, around 2, when he started writing, and actually drawing instruments, we knew that he was fascinated with it," says Orna. "He managed to draw a cello and ask for a cello, and wrote the world cello. And I was surprised, because neither of us has anything to so with string instruments. And I didn't expect him to know what it [a cello] was."
But Jay knew he wanted a cello, so his mother brought him to a music store where he was shown a miniature cello. "And he just sat there. He ...started playing on it," recalls Orna. "And I was like, 'How do you know how to do this?'"
By 3, Jay was still drawing cellos, but he had turned them into notes on a scale. He was beginning to compose, and his parents watched the notes come faster and faster. He was writing any time, anywhere. By elementary school, his teachers had no idea how to handle a boy whose hero wasn't Batman, but Beethoven.
"He hears music in his head all the time, and he'll start composing and he doesn't even realize it probably, that he's doing it," says Robert. "But the teachers would get angry, and they would call us in for emergency meetings with seven people sitting there trying to figure out how they're going accommodate our son."
Jay has been told his hearing is many times more sensitive than an average person's. The sounds of the city need to be shut out manually. But Jay can't turn off the music in his head. In fact, he told us he often hears more than one new composition at a time.
"Multiple channels is what it's been termed," says Jay. "That my brain is able to control two or three different musics at the same time –- along with the channel of everyday life."
"This child told me, he said, 'I'm gonna be dead if I am not composing. I have to compose. This is all I want to do," says Orna. "And when a child that young tells you where their vision is, or where they're going, you don't have a choice."
By the age of 10, Jay was going to Juilliard, among the world's top conservatories of music, on a full scholarship. At age 11, he was studying music theory with third year college students. Jay also takes high school courses at another school – courses his parents say he will finish when he's 14.
Elizabeth Wolff is a concert pianist who works with Jay on his piano technique. Jay writes things he can't even play, and he says he wants to perfect his piano playing, even though he doesn't need the piano, or any instrument, to compose.
What happens when he first hears a tune?
"At first, I just listen to it, and then I start humming it. And then while walking, and I like walking a lot when I am inspired," says Jay. "Because I walk to the beat of the music. For example, if the beat is (piano), I start rocking. ...And I often start conducting as well."
Jay's not a usual 12-year-old, and he knows it. Catching onto baseball isn't as natural as playing piano. Even though Jay's a genius, he's still a kid.
What happens when Jay gets bored? "He gets restless, and then he starts improvising. Last week, he took the Beethoven sonata we're working right now, and decided that everything would be kind of interesting upside down and backwards," says Wolff. "So he took the volume and literally did just that. He can do it for you right now. And I couldn't even follow it. But he actually took the clefs and inverted them. The treble became bass, bass became treble, and did it backwards."
How does Jay rank among other child prodigies?
"To be a prodigy composer is far rarer," says Zyman. "You have to conquer these issues. How do you notate this rhythm? What's the range of the oboe? Can this be played on the piano? How do you compose for the harp? There are hundreds of thousands of bits of information that you need to master to be able to write a piece of music."
Talented composers might write five or six symphonies in a lifetime. But Jay has written five at the age of 12.
When the music enters Jay's head, he has a lot of confidence about what he puts down on paper. Does he ever revise one of his compositions? "No, I don't really ever do that," says Jay. "It just usually comes right the first time."
Sam Adler was a child prodigy himself. Today, he's an accomplished composer and professor of Jay's at Juilliard. He agrees Jay can be great, but only if he is constantly questioning his gift.
"Let's take a great genius in the musical world, someone like Beethoven. When you look at a Beethoven score, it's horrendous. He didn't have an eraser. So, he had to cross it out," says Adler. "And it looks as if, you know, he was never satisfied. And that is something that comes with maturity. And I think that's going to happen to Jay."
But is it fair to say the potential is there? "Absolutely," says Adler. "Without doubt."