Understanding animals, Understanding pain.

Is it really possible for us to understand an animal's experience?  I'm not sure that it is.  Clearly, there are classic arguments like Nagel's What is it like to be a bat, that shows that we will never know the subjective experience of having sonar from just looking at their brains.  I will never know the subjective experience of giving birth.  But this doesn't prevent me from understanding the pain that a woman is feeling when she is giving birth.

How do I understand this?  There are two ways.  1.  I can talk to her and ask her to describe what she's feeling.  This is the most obvious route, but its the less used route, strangely.  (Ma'am, you're currently screaming and there is a child coming out of your uterus, please rate on a scale from 1 to 10, 10 being the worst pain you've ever felt in your life, and 1 being in no pain at all, how you're feeling.  Is it a sharp pain?  Is it an ache?)  2.  The argument by analogy.  She is generally analagous to me.  She has two arms, two legs, a head, etc.  She yelps in pain like I do when I stub my toe.  She's screaming in pain, like I would if I were experiencing something quite painful and traumatic.  So she must be experiencing something quite painful and traumatic.

Both of these investigations into pain however a fundamentally flawed.  The argument by analogy doesn't give us a guarantee, or even a reasonable assurance that the experiences will be similar.  I've been thinking about this a lot lately, because of what my doctor told me recently.  Before my MRI, my doctor said that if he suspects that I have what he thinks I have, that he would be very surprised that I'm not in more pain.  Indeed, I did have what he thought I had, a herniated disc.  And I was in some considerable pain, but I guess I have a rather high tolerance for pain.  And so long as it isn't in my head (I use to get frequent headaches/migranes), I could deal with it.  So whereas my doctor would have been exhibiting much more pain responses (moaning groaning, complaining about the pain, or whatnot), I did not.  Did that mean I was experiencing less pain than he was thinking?  Not necessarily.

The direct route, also is flawed.  After my surgery, the nurse asked me to describe the pain that I was in, and what kind of pain I was willing to tolerate (to help gauge how much medication to give me).  I said I was probably at a 6, and could tolerate an 8.  She looked back at me, and said, "Remember, 10 is the worst pain you've ever experienced in your life."  I said, "Yeah.  This is definately not the worse pain I've experienced in life, but it definately hurts.  But I could definately tolerate it."  This was put to the test later, when I had physical therapy for the first time.  The PT made me stand up and walk around.  Its amazing how much your head weighs.  My neck is in excruciating pain (even with a pre-hit of morphine).  But I walked about 3x farther than the PT expected me to walk.  Ask me to rate that walk on a scale of 1-10, I'd say it was about an 8.  I definately didn't tolerate the walk very well, and even called my PT the "Bad Man" when he came back the next day for another round of torture (the second time included a walk all the way down the hall and back, some exercises with a fake step, and then I pushed him to let me walk up a flight of stairs). 

So what did this all mean in terms of communicating my pain?  Was I experiencing less pain than others?  Was I more tolerant of the pain that I experienced compared to others?  Both?  Neither? I haven't a clue.

So if I can't understand pain of others in any meaningful way, how can I make an argument by analogy with something that doesn't share a body deisgn like mine?  Does it hurt a cow when I poke him with a stick?  I certainly can't ask her.