When we think about drawing, we tend to think of the act in terms of rendering through lines and values, and most basically, via pencil and paper. To draw also has other meanings: "to cause to move;" and this one (which I think is a rather sexy way to phrase it), "to bring toward oneself or itself, as by inherent force or influence."
It could be argued that drawing is the most basic and yet ultimate form of communication, quite literally drawing people together to common understandings. Keith Haring said, "My contribution to the world is my ability to draw. I will draw as much as I can for as many people as I can for as long as I can. Drawing is still basically the same as it has been since prehistoric times. It brings together man and the world. It lives through magic."
We draw because it is magic, and we create worlds through that magic. We draw because, as a communal race of creatures, we need to connect through imagery. We draw to speak what we cannot say, like Van Gogh, who said, "The emotions are sometimes so strong that I work without knowing it. The strokes come like speech." We draw because drawing is limitless in its expression and graphic capacities. We draw because we cannot stop it.
I draw because I see things like these and am, like that sexy definition above suggested, moved:
Why do you draw?