public Object getDomainMt() {
    if (domainMt == DEFAULT) {
      if (defaultDomainMt == null) {
        try {
          defaultDomainMt = (cyc.converseCycObject("(eval " + PPH_DOMAIN_MT.stringApiValue() + ")"));
        } catch (Exception e) {
          throw new RuntimeException("Unable to find PPH domain Mt", e);
        }
      }
      return defaultDomainMt;
    }
    return domainMt;
  }