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xkcd #3084: Unstoppable Force and Immovable Object
(imgs.xkcd.com)
Title text:
Unstoppable force-carrying particles can't interact with immovable matter by definition.
Transcript:
[An arrow pointing to the right and a trapezoid are labeled as 'Unstoppable Force' and 'Immovable Object' respectively.]
[The arrow is shown as entering the trapezoid from the left and the part of it in said trapezoid is coloured gray.]
[The arrow is shown as leaving the trapezoid to the right and is coloured black.]
[Caption below the panel:] I don't see why people find this scenario to be tricky.
Source: https://xkcd.com/3084/
That just moves the problem, what happens if I put a piece of paper between them? Unless they don't interact with anything they still face the same problem.