Reliability and Validity?

Reading about Ebbinghaus' original study on human learning got me thinking about the reliability and validity of his study on himself. Though we still credit him for much of the information we currently know about memory, and many many studies have been performed since that show that his results were reliable and valid, what did his contemporaries think?

He had no subjects, and tested himself. He tried to control as much of his life as he could to keep it constant. He did a good job of creating "nonsense" syllables and reading them at a fast pace, but after many repetitions and the self-designed nature of his study, would he have had a better chance at learning the syllables than an unbiased participant?

We know now of course that these studies can be (and have been) replicated to produce similar results. And I have to give the guy credit; he spent a lot of time doing tedious work so that the rest of us in the psychological field can benefit from his discoveries about memory and learning. Yet I can't help but wonder how bogus it may have looked at the time. Here's this guy, alone in his house, repeating over 2,300 syllables that he printed on cards (how long did it take him to even create the cards?!) to test his ability to learn the material.

It's no wonder that 20 years later, in 1928, Titchener claimed that Ebbinghaus' contributions were the most significant in the field since Aristotle!