What realization does Charlie make during Nemur's presentation at the conference?
As Charlie's intelligence grows he develops a more nuanced and sophisticated understanding of Dr. Nemur and Dr. Strauss. When his I.Q. was low, he merely hero-worshipped them and wanted to please them, as a young child would adults. Later, however, he comes to understand how ambitious both men are. He overhears the following conversation, for example:
Dr. Strauss said that Dr. Nemur was more interested in the Chair of Psychology at Princeton than he was in the experiment. Dr. Nemur said that Dr. Strauss was nothing but an opportunist who was trying to ride to glory on his coattails.
At the conference, Charlie realizes both that Dr. Nemur is old--sixty, and therefore feels under pressure to achieve--and not as smart as he had previously thought:
Contrary to my earlier impressions of him, I realize that Dr. Nemur is not at all a genius. He has a very good mind, but it struggles under the spectre of self-doubt. He wants people to take him for a genius. Therefore, it is important for him to feel that his work is accepted by the world. I believe that Dr. Nemur was afraid of further delay because he worried that someone else might make a discovery along these lines and take the credit from him.
The overriding fact that Charlie gleans is that Dr. Nemur jumped into the experiment with intelligence enhancement too quickly, without enough assurance of success. He begins to realize that he was taken advantage of and used. The experiment was not in his interest but all about career moves for the scientists in question. The old Charlie was not able to make informed consent because he lacked the understanding to do so. The new Charlie has to live with what was done.
Also, Charlie realized that Drs. Nemur and Strauss, particularly Nemur, was more interested in what he would be able to accomplish--for the benefit of people like Charlie, maybe--as a scientist. Here we also see a good example of situational irony--you the reader has important information that the character does not have, or in Charlie's case, doesn't comprehend at the time. If you recall, Charlie was excited about "being used" by the doctors for this experiment. But he didn't understand Ms. Kinnian's comment when she stated, in short, that people are not always what we think them to be so she understand what was being done by the doctors. Charlie did not understand at the time, hence, the reason why, as we would say today, he had an "ah huh" moment at the conference.
Oh, this section is so sad! As a result of the material presented at the conference, Charlie realizes that his gain in intelligence may not last-- that it may be temporary, and he may return to what and who he was before.