IT’S just that we may not be there to see it:

Healing, when it finally comes,
Through medicine, or rest, or cat’s-claw;
Secret workings, lost biology.
Computers break and software fails,
Cars give out and houses crumble,
Yet we hold on to technology,
As though all chance of error
Had been stopped. The body does its work
Without our intervention or
Our will; its testimony one
That we can barely hear or understand.
It is a simple faith:

To hold at last to what we have been told.