What are the eighteen currents of craving that derive from the exterior? When there is the concept ‘I am because of this’, there are the concepts ‘I am such because of this’, ‘I am thus because of this’, ‘I am otherwise because of this’; ‘I am fleeting because of this’, ‘I am lasting because of this’; ‘mine because of this’, ‘such is mine because of this’, ‘thus is mine because of this’, ‘otherwise is mine because of this’; ‘also mine because of this’, ‘such is also mine because of this’, ‘thus is also mine because of this’, ‘otherwise is also mine because of this’; ‘I will be because of this’, ‘I will be such because of this’, ‘I will be thus because of this’, ‘I will be otherwise because of this’. These are the eighteen currents of craving that derive from the exterior.

So there are eighteen currents of craving that derive from the interior, and eighteen that derive from the exterior. These are called the thirty-six currents of craving. Each of these pertain to the past, future, and present, making one hundred and eight currents of craving.

This is that craving—the weaver, the migrant, the creeping, the clinging. This world is choked by it, enveloped by it. It makes the world tangled like yarn, knotted like a ball of thread, and matted like rushes and reeds, not escaping the places of loss, the bad places, the underworld, transmigration.”

Numbered Discourses 4.200 20. The Great Chapter Fondness

“Mendicants, these four things are born. What four? Fondness is born of fondness, hate is born of fondness, fondness is born of hate, and hate is born of hate.