Quote from the post:<p>&quot;There&#x27;s just a small problem.<p>It&#x27;s not with the box analogy: as another commenter noted, it&#x27;s a well known example example you&#x27;ll find in great books like Simon Singh&#x27;s The Code Book.&quot;<p>The problem is not the analogy, the &quot;locked-box&quot; analogy is fine.  The problem is that the math is flawed.  The math is not equivalent to the analogy.