public final String getAgeString()
  {
    if (this.age < 3) {
      return "young";
    }
    if (this.age < 8) {
      return "adolescent";
    }
    if (this.age < 12) {
      return "mature";
    }
    if (this.age < 30) {
      return "aged";
    }
    if (this.age < 40) {
      return "old";
    }
    return "venerable";
  }