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  "body": "\n## Summary\n\nAn initial object of a [[category|A2DE66937D]] is an object with exactly one morphism to every object.\nA terminal object is an object with exactly one morphism from every object.\nThey are the simplest universal properties: the empty set and the one-point set play these roles among sets.\nEach is unique up to a unique isomorphism when it exists, and many constructions are initial or terminal objects of suitable auxiliary categories.\n\n## Explanations\n\n### L1 human\n\nAn initial object is a starting point: from it there is one and only one arrow to anything.\nA terminal object is an end point: from anything there is one and only one arrow to it.\nAmong sets, the [[empty set|0ECVK59Y03]] is initial, because there is exactly one function from it to any set, the empty function.\nA one-point set is terminal, because every set has exactly one function to it, sending everything to the single point.\nAmong groups, the trivial group is both initial and terminal.\n",
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