I do have to admit, I think that Lacan is a little pretentious and slightly over the top with his language. It was really wordy and difficult to understand, and for what reason? All he is really talking about is the age at which a child understands that they are alive. It just seemed unnecessarily verbose. It did make me laugh when he referred to babies as "the human offspring" (71).
I initially used a simple summary of the article that included outside sources and opinions; one being particularly skeptical, which I found to be particularly helpful when I was trying to decipher the passage below.
Here is the passage by Dr. Allen Thiher. (http://www.academia.edu/1539509/Summary_of_Lacan_s_The_Mirror_Stage_as_Formative_of_the_Function_of_the_I_as_Revealed_in_Psychoanalytic_Experience_).
Although I didn't read all of it, I did find an article about a man named Henri Wallon; a theorist that apparently gave Lacan the idea for the mirror theory.