shape and use

Two friends were walking together when one paused to shift the weight of something on her shoulder. The other frowned. "Why don't you drop that?" he suggested. "You'd get further faster."

"Because it isn't a burden," she replied. "It's a shield."

Her companion seemed confused, so she continued: "One is a problem to be solved; the other solves a problem I don't want."

After a moment she added, "Only when it's in your own arms do you know the shape and use of what you carry."

The two set forth once again, taking care to set their pace to one another - as friends do.