Lisp. Lisp is the only language

Why there are other programming languages besides Lisp? With Lisp's macro system you can create any language you need ever. Small, big, finely tuned for your task. Supporting other languages means opposing progress and delaying the inevitable future. There should be only one language and myriad languages at the same time. The one language is Lisp.

>>1

Because this

foldr f acc [] = acc
foldr f acc (x:xs) = f x $ foldr f acc xs
is far more readable than this

(defun foldl (f acc list)
  (if (null list)
    acc
    (f (car list) (foldl f acc (cdr list)))))

Sure you can create a slow bug ridden implementation of half of haskell's syntax on top of a lisp with macros but why not use a language that has nice syntax to begin with?

Sometimes the flexibility of lisp is nice but it comes at a price (homogayiconicity) which you still have to pay when you don't need that flexibility.