CLOS is just as dynamic as Python _and_ fast, at least in SBCL and LispWorks. CLOS is probably the most expressive object system you can find, and if you wanted

CLOS is just as dynamic as Python _and_ fast, at least in SBCL and LispWorks. CLOS is probably the most expressive object system you can find, and if you wanted it fast you would restrict it somewhat to allow for at least some of the dispatch to happen at compile time :)