The Buddha said this:

“Mendicants, I will teach you about craving—the weaver, the migrant, the ubiquitous, the clinging. This world is choked by it, engulfed 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. Listen and pay close attention, I will speak.”

“Yes, sir,” they replied. The Buddha said this:

“And what is that craving …? There are eighteen currents of craving that derive from the interior, and eighteen that derive from the exterior.

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

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 ubiquitous, the clinging. This world is choked by it, engulfed 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.”