There is some subtlety here, for we might suggest that we can easily get around this difficulty by simply placing the missing number a at the front of L. This creates an enlarged listing M containing the annoying number a. However, the underlying problem has not gone away. We can apply Cantor's construction again to introduce a fresh number b that is not present in the new list M. We can of course continue to augment the current list as before any number of times, but Cantor's point remains valid:although we can keep creating lists that contain additional numbers that were previously overlooked, there can never be one specific list that contains every real number.