The Philosophy of Depth

Several threads of conversations with my coworkers have my mind spinning around trying to make sense of different theories about human behavior. I am testing out some ideas they have introduced, trying to apply them to my experience to see if they are true.
Last night, the doctor was testing an animal for propreoception. It happened that the receptionist walked by during the testing and was asking what the difference was between the two different tests the doctor had performed. Dr McFadden explained that one test was for superficial pain and one was for deep pain. The receptionist, who is a very sweet, younger girl whom I do enjoy the company of, but who has some limited knowledge, did not understand the difference between the two types of pain. I was trying to explain it to her and realized the problem was she did not understand the vocabulary.
This really didn't surprise me as much as it should. One would think that someone who made it all the way out of high school would understand these terms. However, I have spent time with this girl outside of work, and our conversation had turned to the things we enjoy, and when I talked about how I liked to study and discuss literature, philosophy, and creative pursuits (I would say "art", but I mean that loosely, since I really don't know much about what most people consider 'art' but I am interested in the imaginative creative process that urges people to produce works), she told me that did not interest her at all. She had also told me she hates to read and really doesn't like to think that much, and is mostly only concerned with appearance and attraction when it comes to the opposite sex. This is who she is, and it seemed foreign to me, but I am fairly open minded and don't really think that someone has to think like me or be interested in everything I am in order to be friends with them. We have enough in common between being mothers, wives, coworkers, and anxious types who are concerned about others perception of us to form enough common ground to have a friendship.
At the end of the explanation to her of the difference between the two types of pain, I was trying to link it to what those terms mean in relation to people, and another one of my coworkers jumped in to the conversation and said something to this effect;
That the terms "superficial" and "deep" are relative to the perception of the subject, and due to this, are subjective terms.
I don't think I agree. Her argument that she used to validate this was that that there are different types of intelligence: common sense, book smarts, street smarts, logic skills, etc. I told her I agreed with that but I didn't see how it related to what we were talking about. She tried again, and this time she told me basically that when a person says another person is superficial, it is only a value judgement and could be based on fallacy. For instance, she says, a person might be concerned with making sure their appearance is top-notch, but it might not have to do with the fact that they believe that appearance is all that matters, but might be in fact that they feel that they do their best work and make the best impression when they feel good about how much work they put into their appearance. I could almost see where she was going with that, and couldn't really come up with a rebuttal, and then the conversation digressed into what she hated about philosophy. I went home thinking about it and researched the terms to see if I could find that those terms are indeed relative. This is what I found on Webster's.

Main Entry: su·per·fi·cial
(1) : of, relating to, or located near a surface (2) : lying on, not penetrating below, or affecting only the surface b British, of a unit of measure : SQUARE 2 a : concerned only with the obvious or apparent : SHALLOW b : seen on the surface : EXTERNAL c : presenting only an appearance without substance or significance - su·per·fi·cial·ly /-'fi-sh(&-)lE/ adverbsynonyms SUPERFICIAL, SHALLOW, CURSORY mean lacking in depth or solidity. SUPERFICIAL implies a concern only with surface aspects or obvious features . SHALLOW is more generally derogatory in implying lack of depth in knowledge, reasoning, emotions, or character .
Main Entry: deep
(1) : extending well inward from an outer surface (2) : not located superficially within the body c : extending well back from a surface accepted as front d : extending far laterally from the center e : occurring or located near the outer limits of the playing area f : thrown deep 2 : having a specified extension in an implied direction usually downward or backward 3 a : difficult to penetrate or comprehend : RECONDITE b : MYSTERIOUS, OBSCURE c : grave in nature or effect d : of penetrating intellect : WISE e : intensely engrossed or immersed f : characterized by profundity of feeling or quality ; also : DEEP-SEATED 4 a of color : high in saturation and low in lightness b : having a low musical pitch or pitch range 5 a : situated well within the boundaries b : remote in time or space c : being below the level of consciousness d : covered, enclosed, or filled to a specified degree -- usually used in combination 6 :

I am not sure that I see anything in these definitions that indicate relativity.
More on this subject and others like it shortly.