static S ai_solveQuestionInSubSpace(T3<S> seed, T3<S> lookingFor) {
  AI_SubSpace subSpace = new(1000);
  ai_setSubSpace(subSpace);
  try {
    ai_postTriple(seed);
    
    int step = 0;
    while (!subSpace.limitReached()) {
      ++step;
      int n = l(subSpace.webs);
      print("Solving question: " + lookingFor + " (step " + step + ", " + n + "/" + subSpace.limit + ")");
      
      pcall-short {
        for (S term : concatLists(keys(subSpace.index), keys(subSpace.websByID)))
          ai_speculate(term);
      }
      
      L<Web> newWebs = cloneSubList(subSpace.webs, n);
      ai_spec_possiblyToActually(newWebs);
      
      S a = ai_text(lookingFor);
      if (a != null) ret a;
  
      if (l(subSpace.webs) == n) break; // No more progress
    }
    
    null;
  } finally {
    ai_setSubSpace(null);
  }
}