This makes me vocalize something Ive wondered about...<p>Whats the smallest subset of lisp which you need to implement in order to bootstrap the language? So, given this small subset, one can implement the rest of say scheme or common lisp or arc on top of.<p>I vaguely recall Sussman or Ebelson implementing car and cadr in terms of lambdas, for example.<p>It seems this should be quite modular, given so many implementations of lisp [ in javascript, PHP, etc now Ruby ]. So that new lisps might be easily brought up over this kernel.