The source of this text about two twins, a skeptic and an optimist, is Pablo J.Luis Molinero, and it is in his book “Morphogeny”.

Two fetuses talk to each other in the womb. One is a believer and the other is not.

Atheist baby: And you? Do you believe in life after birth?
Believing baby: Sure. It is obvious that there is life after birth. And we are here precisely so we can get strong and ready for what awaits us after that.
AB: It makes no sense. There is nothing after birth. Can you imagine what life after birth might look like?
BB: Well, I don’t know all the details. But over there, there will be plenty of light, plenty of joy. And, for example, we are going to eat with our mouths over there.
AB: What nonsense! We have our umbilical cord that feeds us. And yet, no one has returned from that other life. By birth, life is simply ended.
BB: No! I don’t exactly know what life after birth is like, but we will definitely see our mother and she will take care of us.
AB: Mother? Do you believe in mother?? And where is she?
BB: But she’s everywhere! She surrounds us! Thanks to her we live,and without her we are nothing. She takes care of us at every moment.
AB: This is absurd! Have you ever seen her? Me neither! So she obviously does not exist. And if she does exist, why doesn’t she manifest herself?
BB: Well, I do not agree. Because, sometimes,when everything is quiet, then you can hear how she sings … feel how she caresses our world … I am sure that our real life begins after birth.
AB: Well, I’m convinced that there is nothing after birth. That is all irrational.