Sūtra of the Collection of the Father and Son, Selected Lectures (Five)

Original text:大王。若时女人。而于内心。如所思维。彼补噜沙。彼补噜沙。亦生爱乐。由二和合。羯逻蓝生。又复思维。相似和合。而得生者。无有是处。若二女人。无有是处。二补噜沙。亦无是处。若彼彼思惟。而得生者。亦无是处。自体无实。非相应故。

Explanation: Great King, if a woman, in her mind, thinks of another person (a man), and that man also feels love and desire for this woman, then when these two unite, a kalala (fertilized egg) within seven days will come into being. If the two people are not together, being in different places, and merely imagine in their minds that the two of them could unite, with their bodies not in physical contact, and a fertilized egg could be produced—this is impossible. Because there is no actual physical contact, the tathāgatagarbha cannot output the earth element and the five great elements out of thin air to sustain a fertilized egg that does not exist; therefore, no living being is born.

If two women were to unite and produce a kalala, that is also impossible; if two men were to unite and produce a kalala, that is likewise impossible. If any two people long for each other but cannot actually unite, and yet a kalala could be produced, that is even more impossible. Because there is no actual material body and no four great elements, a kalala cannot come into being, since the conditions are not complete.