(The artlcle in the link is called "The Evolution of Consciousness." But G.I. Gurdjieff said it is not evolution in the mechanical sense. The article at the link fails to make this distinction.)
"Man Number 1" is imbalanced in the Instinctive Center, "Man Number 2" in the Feeling Center, and "Man Number 3" in the Thinking Center. All three of these types of Man tend to identify with only one center—Man Number 1 with the instincts, Man Number 2 with the feelings, and Man Number 3 with the intellect. Gurdjieff called these types of Man are "one-centered," not because they lacked the other two centers, but because they rely on only one of them.
Even though only one Center predominates in these types, the other two Centers are active, although in a scrambled, unconscious fashion. Because of this, the three Centers in each Man tend to interfere with one another, preventing the natural development of the person
I don't believe "man 1, 2 and 3" are used to indicate that man 3 is better than man 1, or that man 2 is in the middle. They are simply 3 ways of being "one-centered," that is, of only developing a single center. It means that our consciousness operates in a disintegrated fashion. For example:
This wealthy guy kept parking in the no parking any time area because it was more convenient for him. The city gave him parking ticket after parking ticket, but all he did was pay the tickets (cost of living expense) and continue to park illegally. One day, the city decided to tow his expensive car.
The rich guy caught them towing his car away and blew up, stomping up and down the sidewalk and waving his arms screaming. After his tirade, he explained away his behavior saying with a smile, "That wasn't me, that's not the way I am."
This man is living in one of the lower states of disintegrated consciousness. He has owned parts of himself and disowned other parts of himself claiming that they aren't "him." But they are him, only he hasn't integrated the center responsible for the behavior. He hasn't fully owned himself.
It is necessary to not identify with one type or one center, but to identify with all 3 centers.