I&#x27;d argue that tags provide a more graph-like structure, of which a hierarchy (tree)[1] is just a subset. Symlinks provide an &quot;escape-hatch&quot; to hierarchical systems allowing objects to appear to be in more than one directory.<p>[1] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Tree_(graph_theory)" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Tree_(graph_theory)</a>