throw new RuntimeException(Arrays.toString(stimuli), e);
    }
  }

  private void recurse(int level) {
    // We're going to reuse the stimuli array 3^steps times by overwriting it
    // in a recursive loop.  Sneaky.
    if (level == stimuli.length) {
      // We've filled the array.
      compareResultsForThisListOfStimuli();
    } else {
      // Keep recursing to fill the array.

      }
    }
  }

  private void recurse(int level) {
    // We're going to reuse the stimuli array 3^steps times by overwriting it
    // in a recursive loop.  Sneaky.
    if (level == stimuli.length) {
      // We've filled the array.
      compareResultsForThisListOfStimuli();
    } else {
      // Keep recursing to fill the array.