There are some non-dualists who claim to have an answer to that question. Basically according to them consciousness divided itself in order to experience all the various forms of existence and from the point of view of the (illusory) individual self the goal is to discover that they are in truth nothing other than primordial consciousness (ie. what some call God). Personally I find that explanation circular and unsat…
Maybe it is to say that when you turn and meet the eyes of another you already know that you're the same basic stuff. That's why you open your mouth and start talking. Because you know you'll get an answer back.
Perhaps the text is there to remind you of the significance of that intuition, and to look for generality in plurality, as a useful abstraction. There are other texts that seem to teach you the use of fear, vision, smell and taste, touch and feel.
Maybe it's a manual for your vehicle, and not some philosophical movement.
Just a thought.