Three rings (planar circles) are "linked" together, but you'll notice that none is directly linked with another.
- The red ring is "behind" the yellow.
- The yellow ring is "behind" the blue.
- The blue ring is "behind" the red.
Still, while none is intertwined with another, it is impossible to pull them apart.
Is this a paradox?
Can this really be built?
The only way that the picture is possible is if they are interwined with one another, and without an opening on each of the circles, it would be impossible to pull them apart. The only way that the red can be behind the yellow, the yellow behing the blue, and the blue behind the red is if they weren't overlapping much at all.