Having a headache and not having a headache

Yesterday at 9am, I had a headache. I tried to put it out of mind and focus on other things, and I guess I was successful because the next time I thought about it, it was 10am and I didn’t have a headache. (I’m simplifying and making up times that are approximately right.)

So it went away, but when did it go away? Did it end at 9:10am and I just didn’t notice until 50 minutes later, or did it end at 9:50am? In physics-speak, it was an unobserved variable between the two measurements.

Taking the word “head-ache” literally, I didn’t have a headache at all from 9:01am through 9:59am because I wasn’t noticing it, not perceiving it, and therefore not feeling it. A “pain” that you don’t feel is not pain. How can it make sense to say, “This hurts but I can’t feel it”?

If I noticed I had a headache at 8am and I noticed I had a headache at 9am and the physical mechanism causing it didn’t change over that interval, but I wasn’t noticing it, did I really have a headache from 8:01am through 8:59am?

Suppose that the physical mechanism can be detected by an fMRI machine, and I was being monitored all morning. A neuroscientist could point to an angry blob on the computer screen and say, “There’s your headache. It definitely existed from 7:30am until 9:30am, when the aspirin kicked in. Whether you were aware of it or paying attention to it is another matter.”

The headache that the neuroscientist is talking about is a different thing from the “head-ache” that I’m talking about. In fact, all of our words about sense perceptions and thoughts are doubled like this: my sense of taste is one thing, chemical interactions on my tongue are another, my feeling of excitement is one thing, adrenaline in my blood is another, and my feeling that I understand a mathematical concept is distinct from my ability to answer questions about it[1]. Sure, they’re highly correlated, but that doesn’t make them identical. If your measurements of all the objective criteria disagree with my assertions of my subjective experiences, you might wonder if I’m lying or don’t understand the common usage of the words, but they’re not 100% guaranteed to go hand-in-hand.

This is an elaboration on Reality #5 in my previous essay on Reality and reality-boxes. My point is that the physical reality of chemical interactions on my tongue, adrenaline in my blood, and my quiz results on a mathematical concept are not all there is to say about taste, excitement, or understanding—they’re not the same things as my experience of taste, excitement, and understanding, and they’re not better than/​truer than my subjective experiences of these things. They’re qualitatively different.

In that essay, I included a parable of a physicist and a neuroscientist, in which the physicist took her status as a rational being as a starting point to perform experiments and develop the physics of fMRI machines, and the neuroscientist used the fMRI machine to find the neural correlates of her thinking that she’s a rational being. It would be odd to say that the fMRI reveals a deeper reality, that consciousness and subjective experience is an illusion while physical measurements are real, since it’s our use of consciousness and subjective experience that undergirds and interprets those physical measurements. Not only are they different, but each one swallows the other like some sort of ouroboros.

Subjective reality is an odd sort of reality. Perhaps the neural correlate of my headache existed from 7:30am to 9:30am, but if I only asked myself, “Do I have a headache?” at 8am, 9am, and 10am, then the subjective head-ache could only exist at those times when I was thinking about it. Suppose a part of my mind is thinking about it, which doesn’t occupy the central spotlight of my attention—does that count? The “me” in this subjective experience seems to break down into partial-mes, some of which are content to stay subconscious while others are vying for attention. Perhaps the oddest thing about subjective reality is our inability to communicate it: I know that I have subjective experiences, but I only assume that you do because I’m not a sopalist. But then, if parts of my consciousness can be broken down into subsystems, would those parts have the same kind of skepticism about each other that I have about you?

I’m struggling to write a longer essay on how consciousness is made of pieces of not-quite-conscious thought-stuff below the level of subjective experience, and that it’s also a part of not-quite-conscious thought-stuff above the level of subjective experience as well, that human society is a loosely connected, incoherently thinking brain. But even though it can be broken down into pieces, I don’t want to lose sight of the fact that subjective experience is a primary reality—we couldn’t even approach the other realities without it.

  1. ^

    An example may help: when I finished my first course in thermodynamics, I could pass the tests but didn’t feel like I knew what the subject was about. It’s so different from other branches of physics that I didn’t feel like I had a handle on it. So I took a long walk in order to think about it, and by the end of that walk, I felt like I had a better understanding by categorizing thermodynamics more as a kind of math than as a kind of physics. My ability to solve problems on tests didn’t change: by objective measures, my newfound feeling of insight was rather useless, but it seemed more important to me than my test-taking ability.

    I recognized something similar when I met a mathematician who believed he “didn’t really understand the Pythagorean Theorem.” Obviously, he could solve problems about it, but he felt there was something bigger in it that he wasn’t grasping—maybe something that nobody has grasped yet. If he ever did end up satisfying that itch, chances are that he wouldn’t be able to communicate it directly. Maybe he could introduce a few new theorems or connections with other fields, but whether those theorems fill the hole (and whether there’s a hole in the first place) may be something that happens differently in each individual mathematician.