One is. Two are.

"Seijo, the Chinese girl," observed Goso, "had two souls, one always sick at home and the other in the city, a married woman with two children. Which was the true soul?" [...]

The clouds and moon are the same.
The mountains and valleys are different.
Each is blessed in its own way.
One is. Two are.

(Wumen Huikai, The Gateless Gate XXXV. The case is adapted by Paul Reps and Nyogen Senzaki, while the verse is adapted by myself.)