The 3-Lisp LSP is crucially based on the fact that the expression, environment and continuation of a level can be statically determined and thus pulled out of thin air dynamically without replaying the program from the beginning. This in turn depends on a lot of information about its processor that must be determined even at language design time, or at least at its implementation time. As mentioned before, it depends on the fact that all of the interpreters are known, and even that they are all the same in order not only to use the same reflective procedures in all levels, but also to compile them.