The formula x y (S(x,j) S(y,j) O(x,y))
Evidently, this is not expressing that one of John's sisters is older than
another. (Why? E.g. what if John has no sisters?)
- "decompiles" into 'For all x and y,
if x is John's sister and y is John's sister, then x is older than y'.
- More elegantly, we can re-express this as
'Any of John's sisters is older than any one of them'.
Note that the formula above
would make more "sense" if O were interpreted as "likes", in which case the
formula would say, 'All of John's sisters like each other'.
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