What would it actually take to leave Earth — not for a weekend on the Moon, but forever? This video tests three real generation-ship proposals against five brutal constraints: gravity, radiation, closed-loop life support, cultural continuity across 400 years, and the selection problem — choosing who gets to go. We break down Chrysalis (a 58 km modular ship that sheds stages like a rocket), Proximum (a civilization carved inside an asteroid), and WFP (a self-assembling micro-city based on MIT research). Along the way we confront governance without a homeworld, genetic bottlenecks, generational memory loss, and why shared rituals might matter more than engine specs. The answer isn't one ship — it's three radically different philosophies of what it means to be human in deep space.