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The reason, however, why the nature of things is, in the final analysis, tragic as well as beautiful is that, as Whitehead argues, "every occasion of actuality is in its  own own nature finite. There is no totality which is the harmony of all perfections. Whatever is realized in anyone occasion of experience necessarily excludes the unbounded welter of contrary possibilities. There are always 'others' which might have been and are not" (AI: 356; or, as Hartshorne puts it, "No infima species of possibility ever recurs" [RSP: 118]). In other words, there is, inevitably, tragic loss: God's infinity simply cannot acquire realization! In this sense, Whitehead says, "At the heart of the nature of things, there are always the dream of youth and the harvest of tragedy. The Adventure of the Universe starts with the dream and reaps tragic Beauty" (AI: 381). 

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