S-expressions != &quot;lisp&quot;<p>There is the Common Lisp standard, and those variants really are managed like C compilers are. It&#x27;s pretty great, and the differences are tiny.<p>Scheme has standards -- but yes, due to the language&#x27;s easy implementation many people have made implementations of varying adherence to that standard. This is a <i>good</i> problem, it means people are able to implement their own languages.<p>Finally - clojure&#x27;s rationale is pretty straight forward, and has obviously met an incredible niche in the PL space. I don&#x27;t think it&#x27;s that controversial of an implementation of S-exps.