&gt; higher structures like monads possible<p>What is it about the features that you mentioned that makes monads possible? Lisp (or at lease Scheme and Clojure, which I&#x27;m familiar with) make monads trivially possible -- just as they are in Haskell. They&#x27;re not as useful because those languages have other mechanisms that make monads largely unnecessary, but they&#x27;re no less easy to express.