Henry G. Baker. Metacircular Semantics for Common Lisp Special Forms. ACM SIGPLAN Lisp Pointers V, pp.11–20. 1992.

A response to the criticisms of McCarthy’s semantics for Common Lisp that it didn’t specify the behaviours of special forms, and of the standardisation process of adopting prose definitions that are too “lawyerly” for engineering.

The approach is to define the special forms in terms of other constructions, for example if in terms of nested lambda abstractions to prevent execution of the unwanted branch. This is both useful for understanding and a way of minimising the number of under-defined special forms.

It suggests treating catch / throw as basic, both because other control-transfer forms can be expressed sing them and because it emphasises the interactions that preclude Common Lisp having continuations like Scheme’s. However there’s also an argument pursued that some other structures (like values) provide extra information that can be useful for compilers looking to optimise. It’s a deep exploration of the underpinnings of the language from both theoretical and practical perspectives.