Scheme or Common Lisp?

Yes, it's a “which programming language to leran ???” thread, but this time it's ...more specific I guess?

So I already know C ^{_{and Perl}} and wish to acquaint myself with other paradigms than the procedural and object-oriented ones I've become uncomfortably familiar with (i.e., functional). I also intend to learn Haskell at some point in the future in order to complete the holy trinity of syntaxes.

So, /anus/. Regarding the thread title, what are the differences that you find make you prefer one Lisp dialect to another? Is there even much of a difference? Or did you just choose one as your way of saying, “I've read SICP”?

>>32
You cannot shadow external symbols of the COMMON-LISP package.

Now that you bring it up, there are indeed several problems with code walkers:
1. They need to be able to transform everything to be fully effective, which is difficult with builtins, requires that full source code is available for everything and that everything is written in CL. For example, how many CPS transforms fall flat on their face when encountering MAPCAR?
2. They don't work well together. When two code walkers conflict, you cannot use one in one part of your code and the other in another part like you can with conflicting functions or macros.

In general requiring a global change to solve a local problem sucks. See also ``On the Expressive Power of Programming Languages'' by Matthias Felleisen.