A passage in the Passionate Eye, about a day when Suzanne was only six years old, could describe the physical meaning of "Small Blue Thing":
"So one day I was in the front yard again, playing with a mysterious round object, with a small window through which something blue was gleaming; now I would call it a blown fuse. I shifted it this way and that way and poked at the glass."
This is the same day she was playing with "a stick and a crack" as in "As a Child".
The Passionate Eye - The Collected Writings of Suzanne Vega. Avon Books Inc. 1999

"Small Blue Thing,which to me had a humorous element, and was meant to be more playful than it's been interpreted. It was meant to be almost like a cartoon, like a question that you'd ask a child. 'If you were to describe how you felt, what would you be like?' Or 'If you were a small blue thing, what would you be?' That to me isn't side-splitting funny, but it has an element of whimsy that some people don't look at."
The Performing Songwriter Magazine Interview, by Bill DeMain (http://www.vega.net/perfsong.htm)

"I studied dance from when I was 9 'till about 18, and you spend all day long looking at yourself in the mirror and trying to embody a perfect line or a perfect form in some way, and that's when it became attractive to me. "Small Blue Thing" has that quality of a line about it and that's why I'm so careful about the images, because it's not just enough to write what you feel, it has to have some kind of form to it. Beyond that I can't really say. A lot of it sometimes just comes out the way it comes out but I think sometimes there is a connection between the way I learned to see things as a child, when I was dancing, and the songs [...] I'm always talking about the way things touch and the way something would feel to my senses. Part of my nature as a child was to get lost in the way things felt. If I was washing the dishes I would spend hours at it because I liked the way they felt. I would sit and stroke all the dishes and my mother would be annoyed with me. She had to come in and tell me to stop fondling them. But I've always had that sort of nature that loses myself in whatever it is that I am touching. Or when I worked in the theatre, in the costume department, I would spend hours ironing a piece of fabric. And that's a big part of my nature, that is there in the songs if you listen for it, like in "Small Blue Thing". It's in that song. It's there in my voice sometimes if it's not there in the words."
Interview with Fátima Castro Silva in "Urgent Whispers" (http://watermarks.vega.net/urgent_whispers/index.htm)

Suzanne on how Small Blue Thing can be related with autism:
"The person who's singing the song seems to be preocupied with an interiour world. [...] The tone of it it's circular, kind of objective in the way that it describes feelings, and even though it's a love song to someone else, it's still written from a self contained perspective. It's like someone looking out from an interiour world, and wanting to make contact..."
Radio Interview, Infinite Mind Program

Suzanne on how Small Blue Thing is a mystery:
"Small Blue Thing could be written by a woman to a man or a woman to another woman. There's a question, "What do the feminists think about 'Small Blue Thing'?" I think, "Why should they think anything?" It could be a guy singing to another guy. It could be just about anything. I think I'm more preoccupied with context and character than I am with, say, topical issues. There's some deep part of me that is very cynical and says, "Just because I stand on a stage and say war is wrong, doesn't mean anything." Tell me Reagan's going to listen. I don't believe it. […] Sometimes, when I ask the audience to ask me questions, I'll get strange questions like: "Well, what is the Small Blue Thing?" or, "Why do you feel like a Small Blue Thing?" If I could answer those questions, I wouldn't need to write the songs, I would just explain what I meant."
Generation Magazine, December 9 1986, Suzanne Vega Interview by Allan Rousselle