If you say that "Simply by combination of matter the secretion of the man and woman emulsify and takes another shape, and that secretion, discharge of matter, is due to lust," that is all right. But unless there is the living spark, soul, within that material combination, there is no pregnancy. The pregnancy will take place when there is actually living soul within this material creation, material combination, emulsification. That is the knowledge we get from Vedic sources. Karmaṇā daiva-netreṇa jantur deha upapatti (SB 3.31.1). Jantuḥ, the living entity, is getting a type of body by the karma. It is not simply lusty combination. Because the living entity has got his karma, therefore one is born as Mr. Ford, and one is born something else. It is due to karma. Otherwise, why he's born one rich and poor? There must be some consideration.
So that they do not find. They do not . . . they have no eyes to see. They simply see the superfluous combination, permutation. No. That superintendence is explained in the Bhagavad-gītā, mayādhyakṣeṇa prakṛtiḥ (BG 9.10). The Bhāgavata also says daiva-netreṇa. Daiva-netreṇa means "under the leadership of the Supreme." As soon as one dies, gives up this body—he does not die; he changes the body—now, the next body . . . here is a duration of changing body. Say for a hundred years the changing is going on. Then, after that, when he changes this body, then there is daiva-netreṇa, the judgment: "What kind of body should be awarded this living entity." That is called daiva-netreṇa.