static L<Map<S, Lisp>> lispTruthMatches(Lisp pat, S... variables) {
  Set<S> vars = asSet(variables);
  L<Map<S, Lisp>> out = new L;
  for (LispStatement l : values(lispStatements_cached()))
    addIfNotNull(out, lispMatch(pat, l.term, vars));
  ret out;
}