No Moving without Packing Something

The perfect inter-convertibility
Of energy and matter on a spacetime
Curve’s all well and good, but it’s strain that measures

The nature and metes out the living of all
So-far surviving things. How much strain is there
On the system, the bones, the capillaries,

The roots, the tendons, the heart? What can you take?
How much strain to be alone, to be social,
To raise your children, pay your debts, change your sheets?

Those are your measures—not energy, matter,
Not even money most fungible. What strain
Packs your environment? How much can you take?