Passage Summary: Because Asian elephants never have all their feet off the ground at once, they aren't technically running.

Conclusion: Asian elephants do not actually engage in the act of running.

Reasoning: These elephants always keep at least two feet on the ground, even when they accelerate by changing their stride.

Analysis: There is a clear gap here between the physical description of the elephant's movement and the definition of running. The argument assumes that if you don't have a moment where all feet (or perhaps most feet) are off the ground, you aren't running. To guarantee the conclusion, we need a rule stating that running requires a period where fewer than two feet are on the ground.