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by a333999 497 days ago
> any description purely in terms of pairwise relationships would miss the fact that the three rings are connected.

Here is one:

A is connected to B

B is connected to C

C is connected to A

This is a description in terms of pairs, and from it is trivial to deduce how the rings are connected.

2 comments

But they're not pairwise connected.

In the text:

   If you only consider two of the rings and ignore the third, then any pair can be smoothly separated.
and from looking at the diagram. Carefully looking.
The pairwise description you list correspond to a different link, namely, one where each pair is actually connected. For the shown rings, the 'correct' description would be:

A is not connected to B B is not connected to C C is not connected to A A, B, and C are connected

This seems paradoxical, but the paradox is resolved by the 'higher-order' linkage.