对于普通读者而言，建议重点关注However, only in theory, i.e. in McCarthy's papers! :). in practical terms, I don't think there is any practical Lisp, more than toy examples, based on only those first 5, or 9 or 7 or how many forms McCarthy thought at some point in time are "basics". Emacs does not have statements on which are "elementary forms". C core implements ~1700 of "primitive" forms. Graham came up with 17 for Arc. Common Lisp has 25. Now, I have never used Arc, but I am sure that none of Common Lisp implementations in Common Lisp are implemented directly on top of only those 25 so called "special operators", even though, in theory that might have been the idea. Of course I don't know for sure, I discovered Lisp after the Lisp, and am just learning this myself, but to be practical you have to talk to the outside world, and outside world is often a bit more complex than what those 25 forms cover.However, only in theory, i.e. in McCarthy's papers! :). in practical terms, I don't think there is any practical Lisp, more than toy examples, based on only those first 5, or 9 or 7 or how many forms McCarthy thought at some point in time are "basics". Emacs does not have statements on which are "elementary forms". C core implements ~1700 of "primitive" forms. Graham came up with 17 for Arc. Common Lisp has 25. Now, I have never used Arc, but I am sure that none of Common Lisp implementations in Common Lisp are implemented directly on top of only those 25 so called "special operators", even though, in theory that might have been the idea. Of course I don't know for sure, I discovered Lisp after the Lisp, and am just learning this myself, but to be practical you have to talk to the outside world, and outside world is often a bit more complex than what those 25 forms cover.