Actually it comes to the point where his gift of intellectuality becomes a rapidly increasing obsession and blinds him to his identity, which clearly comes to the surface in the restaurant, where he ironically enough laughs at himself (at a retarded servant in a restaurant). This is the first time Charlie perceives what the operation has brought him. At this time, and after Algernon's dead, Charlie's illusion bursts, because he's confronted with the history(, which could repeat itself, ) he has pushed and banned out of his mind a long time ago. You get the impression he has been lying in coma for a while, in his own world, completely unaware that one day he had to deal with the inevitability, facing ( the comeback, when after Charlie's death) his old self. His new lifestyle as an intellectual is instantly impaired by the consciousness and the suppressed knowledge, that he used to be an inferior just like the servant at the restaurant. Before Charlie agrees to go through with the operation he regards it as a second chance on being what he desires; being smart and having the possibility to understand and to lead a normal life; he wishes to be like everyone else. Also the circumstances don't offer him any other view on the operation; All his other classmates weren't offered the chance, Miss Kinnian convinces him that it is an opportunity he must capture and the docters give him the impression that the experiment will be medically relevant and profitable for advancement, which implies him for the first time being of any benefit. I think the thought of making himself useful also attracted Charlie but most of all he wanted to become intelligent. After the experiment he still acquires more knowledge and becomes independent, but he also becomes aware of the many consistencies he has suffered and the losses the experiment has included. He's conscious of not having accomplished a standard life.
