Cotheca is a city of fanatical collectors. Its citizens are united in the cause of building the ultimate Collection, an exhibition without parallel. It is their aim to preserve for posterity everything human – all human life, all human artefacts, everything made or touched by humans. They envision the world as a museum, and themselves as its curators.
The people of Cotheca are the most pacifist in the world. Since the Collection, encompassing all human life on Earth, must for completeness' sake include the Earth itself (and since no smaller territory would suffice to display all its contents), the Cothecans' ultimate ambition is, admittedly, world domination. Yet they have no intention of taking it by force – they don't want to damage any of the exhibits. And they don't want the exhibits damaging each other, either. Wars, to them, are acts of unimaginable vandalism. Injecting you with embalming fluids is nothing less than a Cothecan's duty as a curator of the Collection, but overpowering and restraining you in order to do it would be like roughing up a Ming vase.
It's therefore very easy to capture any Cothecans who leave the city (but check them carefully for syringes!), and although no tourist has ever returned from Cotheca we know quite a lot about their society. (Cothecans are very happy to discuss their ways with outsiders, hoping no doubt to recruit others to their cause.) They prize individuality highly, since it is each person's uniqueness that justifies his or her inclusion in the Collection. Identical siblings are taboo, and after the firstborn twin or triplet is delivered, the "duplicates" are discarded, unnecessary. There is no question of swapping with hypothetical rival Collections – the Cothecans will not countenance rivals, since this would threaten the Collection's own uniqueness. It is an article of faith that once completed, the human Collection will itself be collected by the curators of some vast interplanetary museum. This at least answers the question of who the Cothecans plan to display their Collection to.
Each Cothecan is expected to live a responsibly healthy life, breed the next generation of curators, perform such curating duties as they can and finally surrender their bodies for cataloguing and archiving. This generally happens in late middle age, while they are still in reasonably good condition. They have enough specimens of old age among the tourists and explorers they've collected. Violent criminals, rare as they are in Cothecan society, are subject to summary preservation and are displayed publically alongside informative descriptions of their acts. When all other specimens have been archived in the Collection, the curators will archive each other – writing up their lives on display cards, assuming dignified postures and being pumped full of embalming fluids. Finally, her work done, the last curator will write out her own card, take a last wistful look at the perfection around her, and commit an act of self-preservation.