Peru u-revu is the sacred responsibility to have children. This responsibility is foundational to the human experience, and to the experience of being Jewish. Of Mirrors & Apple Trees: The Lomdus of Peru u-Revu comes to analyze: a. the philosophy of this mitzvah, b. how this philosophy is derived from analyzing the mitzvah's parameters, and c. how this philosophy is derived from analyzing the mitzvah's interrelationship with some of the Torah's other mitzvos.