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Foundation/SimonsVsFine: cannot be made up of individuals of the same category - better R-families - normally include continuants and events (problem: then again no sum can be formed)- generic dependency: Often only something vague is required: E.g. any oxygen molecules.
Foundation/Husserl: explains best what the whole complex holds together. Connection/Husserl: ultimately purely formal - if objects cannot exist without each other, it is pointless to look for a chain.
Parts Oxford New York 1987