OK, point taken about #1.  It is valuable to have the basic axioms and then separate syntactic sugar.<p>But #2 and #3 are what I would call bootstrapping problems... in other words, there is a reason that C is the foundation of computing rather than Lisp.  I don&#x27;t think anybody really thinks otherwise anymore.  But for example, set-cdr! is not in the lambda calculus, and you need it even for basic things.<p>Likewise, Scheme implementations have mutable hash tables, but they&#x27;re written in C and not Scheme.  I don&#x27;t know how you even write a hash table based on cons cells rather than O(1) indexing.<p>Regarding #4, here is a good link.  The basic idea is that macros could just be functions on lists, and then you get composition of macros like you have composition of functions.  Paul Graham incorporated this into Arc.<p><a href="http:&#x2F;&#x2F;matt.might.net&#x2F;articles&#x2F;metacircular-evaluation-and-first-class-run-time-macros&#x2F;" rel="nofollow">http:&#x2F;&#x2F;matt.might.net&#x2F;articles&#x2F;metacircular-evaluation-and-f...</a><p>My point is you could say Scheme sits at a somewhat awkward place between &quot;not foundational enough&quot; (not fully bootstrapped) and &quot;awkward in practice&quot; (compared to say Python).  Though I wouldn&#x27;t go as far as to say that... Obviously it was groundbreaking work that influenced Python and R and tons of stuff we use today.  It&#x27;s outstanding research, but it feels like it has been almost fully incorporated into the computing culture now.