> you would never (def x 1) and then (def x 5) in a running program Right, I understand. It was the way the author stated 'x never changes' that made me belie

> you would never (def x 1) and then (def x 5) in a running program Right, I understand. It was the way the author stated 'x never changes' that made me believe he doesn't understand the difference between binding a name and changing a value.