Greenspun&#x27;s Tenth Rule is a joke (there aren&#x27;t even any other rules numbered 1-9). It&#x27;s not meant to be taken literally.<p>The point is that low-level languages like C and Fortran (and today, Java) are underpowered, and any sufficiently large project will evolve to the point where someone builds a (often vaguely Lisp-like) scripting language on top of it to allow developers to raise the level of abstraction, maybe without even realizing that&#x27;s what they&#x27;re doing.<p>I have seen this in action, a lot of companies build internal, proprietary scripting languages on top of their low-level programs. They may start out as configuration files, a build system, preprocessor macros, or a DSL, but over time as features get added they accidentally become Turing-complete, and eventually someone writes an interpreter and now you&#x27;ve invented something that serves the same purpose as Lisp, only worse.<p>More here: <a href="https:&#x2F;&#x2F;sites.google.com&#x2F;site&#x2F;steveyegge2&#x2F;the-emacs-problem" rel="nofollow">https:&#x2F;&#x2F;sites.google.com&#x2F;site&#x2F;steveyegge2&#x2F;the-emacs-problem</a>