Are you one or many? Most people call themselves I not we, but if “I” refers to the body, it is a collective of cells that constantly die and are replaced. Skin loses about a million cells a day and it is just one organ. Red blood cells live maybe four months, white blood cells a year or so, skin cells a few weeks and colon cells a few days. Where is the “I” in a bunch of cells that come and go? That some nerves may last a lifetime led one biologist to conclude that I am my nerves:
“The Astonishing Hypothesis is that ‘You’, your joys and your sorrows, your memories and your ambitions, your sense of identity and free will, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules. As Lewis Carroll’s Alice might have phrased it: ‘You’re nothing but a pack of neurons’.” (Crick, 1995)
If so, should I call myself We? If “I” is a medieval error, like that the earth is flat, should we now say We did this instead of I did it? If you don’t want to refer to yourself “We”, then welcome to the hard problem of consciousness (Chalmers, 1996), that we experience life as a single “I” even though we are physically a collection of cells.
Neurons respond to one light frequency as “red” and another as “blue” but why is red this experience and blue that one? Nothing in neuroscience requires the processing of different light frequencies to give experiences, so what causes redness and blueness? The hard problem is that we don’t know why sensory input creates an experience as well as a response.
Imagine a scientist who knew all the facts there are to know about blue from a monochrome screen, such as how neurons analyze blue light frequencies (Jackson, 1982). Yet if she then sees blue for the first time, it’s a new experience, so what does she now know that she didn’t before? The hard problem is that the facts of blueness don’t explain the experience of seeing blue.
The Islamic scientist Avicenna proposed a thought experiment: a man floating in a void with no body sensations at all has no awareness of his arms, legs, heart or any other body part but still knows he exists. The floating man knows I am, even if all inputs stop. The hard problem is that the observer remains even when nothing is being observed.
We consider ourselves conscious, and so divide reality into beings that are conscious like us and matter that isn’t, but where is the line between? If people are conscious, are dogs, or insects or plants? If I am conscious, is the baby, fetus, or the one cell I grew from also conscious? Dividing reality like this gives an explanatory gap between the matter that makes our body and our experience of it (Levine, 1983). I observe a room of matter but if I am in the room, am I also matter? If what applies to matter also applies to me, am I also a thing?
Conway’s free will theorem is that the same rules apply to everything, so either everything is conscious or nothing is (Conway & Koch, 2006). If we are conscious, so is matter, and if matter isn’t, then neither are we. That we are conscious but the universe we came from isn’t, is illogical. The hard problem is that no property of matter predicts the observer experience we report.
After centuries of discussion, the hard problem today is no easier than it ever was:
“The question of how matter gives rise to felt experience is one of the most vexing problems we know of.” (Brooks, 2020)
Science still can’t explain how we can experience physical events in a body made of matter.