 about, in
&gt; which case this is a good opportunity to learn my mistake.
&gt;
&gt; I was under the impression that variable expressions like:
&gt;
&gt; (forall ?x (=&gt; (car ?x) (has-wheels ?x)))
&gt;
&gt; were lambda expressions largely because they did involve variables.
&gt; Please explain my error.

The expression above is simply a sentence in a particular first-order
language.  A lambda expression is a property-denoting (or function-, or
relation-denoting, depending on the flavor of lambda calculus)