Twitter proof: a terrible shoe shop


In this post I will show how our intuition can be fooled, even by the simplest geometrical problems... The proof is related to a real-world problem, even though an uncommon one. Say we go to a shoe shop and we try on a new pair of shiny shoes; most of the times we will want to check them out by looking into a mirror. Suppose that said mirror is too high on the wall and you can't see below your knees...
What should we do next? Do we take a step forward or a step backwards?

Claim: Unless we bent our back, taking a step forward or taking a step backwards does nothing.

Twitter proof: for this proof, an image suffices.
Did you get it? Let me know in the comments section!

  - RGS

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