IIRC the author wanted simplicity was the reason invoked by the author. Newlisp has dynamic scoping and contexts (namespaces), in which you get lexical scoping, plus other features. For instance when you want to close some function over some variable, one creates a new function by expanding the free variables inside the existing function (or lambda), to their local value at runtime. Which shouldn't be too much expensive if used in a smart way, I guess. This might be a bit weird, this and the Only One Reference (ORO) memory management strategy, but Newlisp executable is very small with regards to the craptons of functions that are included in the core. I could make it on a low-end 32bits micro-controller, where few interpreters can pretend to run at acceptable speeds and/or fit (a couple MB of flash space). The context and ORO thingies may be use in conjunction to use what they call "FOOP", for functional object oriented programming. The association of both paradigms, in theory, should let users scale to larger applications, assuming they can grok it.