The Gardener's Season

For thirty years, a small literature has asked whether intelligence could participate in cosmic reproduction. Its founding paper also drew its boundary: Crane observed that in a cosmology where each black hole births one universe, a civilisation manipulating existing black holes changes nothing — only the manufacture of new holes closes the evolutionary loop. We show that in a two-parent cosmology, where child universes arise from black-hole mergers, this boundary inverts. What one does with existing black holes becomes everything: an intelligence that influences which two holes merge chooses the pairing of a child’s parents — and with it, under the inheritance scheme of the companion paper, the child’s traits. The single-parent gardener can only clone; the two-parent gardener can graft. The engineering problem correspondingly moves from particle physics (manufacturing a hole, at absurd energies) to celestial mechanics (influencing which inspirals complete — matchmaking, at astronomical patience). Two demands are answered in the essay’s own pages: a causal account of how an exterior merger can be reproductively meaningful to interiors formed long before (the daughters’ throats fuse, and the junction is conjectured itself to bounce, producing the child as their joint issue), and a defence of the lever against vacuity — the measured merger rate amounts to roughly one event per galaxy per half-million years, so the bar for gardened significance is startlingly low, and the binding question is per-merger feasibility, which is unanswered rather than answered in the negative. The shared calendar of minds and mergers is retained in a single section, presented as interpretation of a timing that stellar physics already explains, at order-of-magnitude precision. Revision history. GS 1.2 → GS 2.0 (June 2026). The paper was reframed around a single structural finding: the manufacture-to-matchmaking shift as a consequence of two-parent cosmology. κext (chirality observable from the parent universe’s exterior) and κint (interior transient in the child’s causal past) were introduced as distinct notations; their causal disconnection is the programme’s identified break point. A second independent break point was added: the kick is generically erased by inflation even if the causal route closes.