Why it is wrong to say that "The rain is falling."

The falling is the rain 

The week after I get back from Istanbul I go on a meditation retreat with Thich Nhat Hahn, the Vietnamese Zen master. I've been studying with him off and on (mostly off) for eighteen years now. I will sit for a week in silence, listen as he speaks, but I end up talking more than planned. My dharma discussion group's focus is addiction, and a handful of us addicts climb a great maple tree each afternoon to talk among the branches until sunset.

Thich Nhat Hahn says it is a mistake to say, "The rain is falling," to say, "The wind is blowing." What is rain if it is not falling? he asks. What is wind if it is not blowing? The falling is the rain, the blowing is the wind. The next day, in the tree, I bring it up. He's talking about impermanence, someone says. It's the same reason we climb trees, someone else offers -- it's that we were once monkeys.

From The Ticking is the Bomb by Nick Flynn.