The back composed
of a large and complex group
of muscles that work together to support the spine, hold the body upright, and enables the body's torso to move,
bend, and twist
in a
number of directions.
Revkin When you have endpoints that you don't know how to reach, chanting
numbers like [four degrees, or] two degrees, or 350, or 80 by 2050, is less useful than saying, what are the traits
in societies and individuals that I can work on that give us the best chance
of bending curves
in directions that are «good»?