> Common Lisp is not a ‘pure’ functional language, however, such as Haskell; it is multi-paradigm like OCaml. You can choose to use the functional paradigm in C

> Common Lisp is not a ‘pure’ functional language, however, such as Haskell; it is multi-paradigm like OCaml. You can choose to use the functional paradigm in Common Lisp if you like, but you can also use Procedural, Object-Oriented, Event-Oriented, novel new paradigms like Aspect-Oriented, or mix and match to your hearts content. __Strict Functional programming languages do not offer this flexibility__. "Strict functional programming languages" could be interpreted as languages with strict evaluation. But I guess it is clear in this context that they mean pure functional languages (or pretty rigorous with regards to purity).