How?
The third personality snaps on people, rants, lacks compassion for others, and is somewhat of a hellraiser. He might try to save the world, but he wouldn`t mind seeing it burn either.
Og Elliot is the COMPLETE opposite. He`s more of a keep his thoughts to himself type guy. He`s like an introvert who wants to save the world he`s an outcast in. He definitely has compassion for others
Watch that scene when Elliot is all up in Tyrells face. Look how aggressive he is. I think he even said he don`t give a fukk about him. THAT`s personality #3
Not long after that (same scene i think) Elliot sympathises with Tyrell, and shows him compassion, and by the end he tells him (paraphrasing) i don`t think i could just leave you here. THAT`S OG Elliot.
There`s instances like this throughtout the series. Some others posted examples in this thread. I think this season though, we`re seeing personality #3 a bit more than previous seasons.
Mr. Robot is like the medium between the two.