The Giver is the only one in the community who has access to all of the books and memories that ever existed. Compared to the instructors at Jonas's school, the Giver sees the instructors as illiterate, metaphorically. Yes, the instructors have been educated in one part of the community, but that is all their knowledge and understanding are limited to. Further, The Giver has experienced more pain, suffering and joy than any adult in the community could ever comprehend; and even if they did experience those things, they would probably die from shock since they have been so shelterd their whole lives.
Finally, The Giver explains that "without the memories it's all meaningless. They gave that burden to me" (105). What he means is that an instructor can memorize all of the facts and figures in the world but without a true reason to apply those facts to life, then they aren't anything useful. A wise man once said that math and science are what makes the world go 'round, but love is what we live for. Jonas's community doesn't have love. They have peace, but they do not know true joy because they do not experience pain--that if The Giver to handle alone.
I agree with Tinicraw. Without memories, knowledge IS meaningless. What I mean by that is: Think about all of the books that the Giver has. He could learn about anything that he wanted! But that is meaningless unless he has performed some of the actions himself. Like, say that the Giver wanted to learn about how toasters work. (Random word :D ) He could read book after book about toasters, and how they work, but learning those things are meaningless and pointless unless the Giver himself has looked at a toaster and messed around with it. He would sort of comprehend how toasters work, but he would never truly understand how they work unless he has experienced working on a toaster.