In practice

In practice, however, the type system constrains the programmer in many ways that are unacceptable to Lisp programmers: data cannot be interpreted as programs, lists must be homogeneous, and functions are not easily redefned without recompiling other dependent functions.

>>9
Untrue, you can write an interpreter in most languages. You can also write compilers or even JITs, but things get a lot more complex and unportable there.
LISP interpreter - one page of code
Haskell interpreter - what?!!