The Exponential Function

I am still pondering my way through the ramifications of the "Phoenix" paradox. If it is really true that GDP growth correlates to the rate of change of the change in loans outstanding, what Biggs, Mayer et al call the "impulse" and what I would call dSuck/dt, then it may be interesting to keep in mind that the derivative of the exponential function is.... the exponential function.

Also, it would seem that if this is what is really required for GDP growth, we're seriously screwed. Why would that be? Read this post from Fickett GDP growth is compatible with shrinking credit and then try to imagine a world where we can keep on growing without blowing up.